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Handbook for petroleum and chemical engineers, this book is useful for the design engineer and for the processing of crude oil and gas processes. it outlines the basic steps taken in the dri…Deskripsi lengkap
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VOL. I INDEX OF SECTIONS lor Ready Reference S E C T IO N
■ Vv PAGES
1. M IN E R A L O G Y ..........................................................................................
1 -5 3
2. G E O L O G Y A N D M IN E R A L D E P O S I T S .....................................
1 -3 4
3. E A R T H E X C A V A T IO N ..........................................................................
1 -1 9
4. E X P L O S IV E S .............................................................................................
1 -3 2
5. R O C K E X C A V A T IO N ............................................................................
1 -2 9
6 . T U N N E L IN G ..................................................................... ........................
1 -2 9
7. S H A F T S IN K IN G IN R O C K ...................................... ......................
1 -3 3
8 . S H A F T S IN K IN G IN UN STABLE A N D W A T E R B E A R IN G
G R O U N D .................................................................................................
1 -2 5
9. B O R IN G .......................................................................................................
1 -7 1
10. P R O S P E C T IN G , D E V E L O P M E N T A N D E X P L O IT A T IO N O F M IN E R A L D E P O S IT S .............................................................
1-6 4 0
10-A . G E O P H Y S IC A L P R O S P E C T IN G ......................................................
1 -4 2
I t U N D E R G R O U N D T R A N S P O R T ........................................... ..
1 - 47
12. H O IS T IN G P L A N T , S H A F T P O C K E T S A N D O R E B I N S . 1 - 1 3 6 13. D R A IN A G E O F M I N E S .......................................................................
1 -2 1
14. M IN E V E N T IL A T IO N ...........................................................................
1 -6 6
IN D E X .............................. ............................................................................
1 -8 3
MINING ENGINEERS’ HANDBOOK
MINING ENGINEERS HANDBOOK W R IT T E N B T A S T A F F O F F O R T Y -S IX S P E C IA L IST S U N D E R T H E E D IT O R S H IP OF
ROBERT PEELE L a t e P r ofesso r E m e r it u s o f M in in g E n g in e e r in g in th e
S ch ool o p M in e s , C o l u m b ia U n iv e r s it y
W IT H T H E C O LL A B O R A TIO N OF
JOHN A. CHURCH M in in g a n d M e t a l l u r g ic a l E n g in e e b
'
1
THIRD EDITION
IN TWO VOLUMES' VOL. I
JOHN
WILEY
& SONS,
I
n c
New York • Chichester * Brisbane 8 Tbronto
PUBLISHER’S PREFACE
C o p t b i g h t , 1 9 1 8 , 1 9 2 7 , 1941
BY
JO H N W ELEY & SONS, I nc .
1918 Copyright renewed 1945
A ll Rights Reserved Reproduction or translation o f any part o f this work beyond that permitted by Sections 107 or 108 o f the 1976 United States Copy right Act without the permission o f the copyright owner is unlaw ful. Requests for permission or further information should be addressed to the Permissions Department, John Wiley & Sons, Inc.
Copyright Canada, 1941, International Copyright, 1941 J o h n W i l e y & S o n s , I n c ., Proprietors
All Foreign Rights Reserved Reproduction in whole or in part forbidden
THJBD EDITION
20
ISBN O’471 67716 7
P B X N T R 9 I N T H E TTN ITBD S T A T E S OF A M E B IC A
In making plans for new editions o f our handbooks in mechanical engineering and in electrical engineering, it soon became clear that engineering science and practice had developed to such an extent that handbooks were growing beyond all practical bounds. They had become both bulky and inconvenient and contained much duplicated material. In order to solve the problems presented b y these conditions, the editors o f our various handbooks were asked to serve as an advisory editorial board. This board recommended, first, that the fundamental material underlying all engi neering be published in a separate volume, and, second, £hat the existing handbooks as they are revised be issued in several volumes containing material closely related to the specialized branches o f engineering. A s a result o f these recommendations, the Wiley Engineering Handbook Series has been initiated, which in the beginning will comprise the following: Eshbach’ s “ Handbook o f Engineering Fundamentals” ; Kant’ s “ Mechanical Engineers’ H andbook” in tw o volumes, viz., “ Pow er” and “ Design and Shop Practice” ; Pender’ s “ Electrical Engineers’ H andbook” in two volumes, viz., “ Electric Pow er” and “ Communication and Electronics” ; Peele’ s “ Mining Engineers’ Handbook.” This division has also made it possible to devote more space to the various topics so that the entire new series of handbooks contains mqte complete information-on all topics than heretofore has been possible. I t is our hope that this new plan will give engineers information that is more useful, more -complete, and in more convenient form. J o h n W e lb y & S o n s , I n c .
PREFACE TO THIRD EDITION The first edition of this book was published early in 1918. In preparing the second edition, issued in 1927, many changes in subject matter were found necessary, as set forth in the preface to that edition, and references to them need not be repeated here. Most of these alterations were called for b y the progressive modifications of mining methods and appliances, and the development of new methods. Much new matter was added, some of the older text omitted, and some sections o f the book were almost entirely rewritten. Rewriting the present edition made necessary the radical revision o f text and illus trations of Sections 3, 4, 5, 8 , 10, 10A, 12, 14, 15, 16, 22, 24, 26, 27, 32, 33, 35 and 40, together with minor changes in many other parts of the book. Especial attention is called to the following: (a) important new matter throughout Section 10, on further changes in practice in “ Methods of Mining,” b y James F. McClelland, Vice President of Phelps Dodge Corp; (6) new articles 24 to 28 of renumbered Section 45; (c) a valuable new Section 44, o n “ Petroleum Production,” b y S. F. Shaw, has been added; (<2) the marked advance o f '“ Geophysical Prospecting” during the past decade has made advisable the addition of an entirely new Section 10A, on that subject, b y Frederick W . Lee, of the 17. S. Geological Survey. This Section replaces, in greatly expanded form, the data formerly contained in Articles 3 and 4 o f Section 10; (e) Section 14, on “ Mine Ventilation,” has been almost wholly rew itten b y George E . McEIroy, of the TJ. S. Bureau of Mines; (f) radical revisions have also been made in Section 12, “ Hoist ing Plant, Shaft Pockets and Ore Bins,” b y Professor Philip B. Bucky, o f the Columbia School of Mines, and o f Section 15, “ Compressed A ir Practice,” b y A . W . Loomis, of the Ingersoll-Rand C o ; (g) the wide development o f methods and devices for underground handling and conveying of mineral has led to the transfer o f m ost o f the data, formerly in •Article 92 o f Section 10, to Section 27, the first part of which has been rewritten and expanded, b y Walter M . Dake, Research Manager o f the McGraw-Hill Publishing Co. The preparation of this edition has further required resetting the entire book. A larger format was necessary, since the two volumes o f the Third Edition are N os V I and V II o f the new Wiley Engineering H andbook Series. This change, together with the extensive revisions of text already referred to, lias consumed much more time and labor than were required for the second edition. T o the list of deaths of the original Associate Editors, noted in the preface to the second edition, the following names must now be added: Edwin S. Jarrett (Sec. 8 ), F. Ernest Brackett (Sec. 14), Richard T . Dana (Sec. 15) T. R . Woodbridge (Sec. 29), E. J. Hall (Sec. 30), and Charles H . Burnside {Sec. 36). For various reasons, a number o f associate editors o f the second edition were unable to serve again. Their places have been taken b y : Clinton L. Bogert (Sec. 3), Samuel R . Russell (Sec. 5), Charles F. Jackson (Sec. 6 ), Ralph H . Chambers (Sec. 8 ), Philip B. Bucky (Sec. 12), George E . M cEIroy (Sec. 14), A. W . Loomis (Sec. 15), Walter M . Dake (Sec. 27), J. B. Morrow and staff (part I of Sec. 35), and Theodore Baumeister, Jr. (Sec. 40). For further information as t o these accessions to the list oi Associate Editors, see the Table of Contents. It is a pleasure to acknowledge the efficient collaboration o f m y friend John A . Church, in connection with this new edition. Besides being tiie Associate Editor o f Section 7, on “ Shaft Sinking in R ock,” he has done a large amount of work in revising manuscripts,, as received from the contributors to the book, and in the preparation of illustration^ for the engraver. R obebt P eelb N e w Y obe ,
M arch, 1941
vii
PREFACE TO FIRST EDITION There is a considerable literature o f mining, comprising treatises, textbooks, m ono graphs, papers published in the transactions o f engineering societies, and the contents of the mining periodicals. The treatises and textbooks are largely descriptive, and are intended chiefiy for students. Among the best known are those o f Foster, Hughes, Haton de la Goupilliere, Köhler» Cambess6des, Gallon, Ponson, Bulman and Redmayne, Bailes, Boulton, and Pamely. Though many of these books are antiquated in their engineering features, some o f the older ones (as those o f Callon and Haton) contain much that is still o f value, and mining engineers would do well to have acquaintance with them. Besides the general treatises there are the more recent monographs of Truscot, Hatch and Chalmers, and Denny, on the Witwatersrand goldfields, Charleton’s “ Tin Mines o f the W orld,” H oover’s "Principles o f Mining,” Finlay’s “ Cost o f Mining,” and a number of useful books on specific subjects relating to mining, or to the mechanical engineering of mines. A valid reason fo r bringing out a new Mining Engineers’ Handbook m ay be found in the fact that the two already in existence either omit, or treat too briefly, many sub jects which constitute important parts o f the professional equipment of the present day mining engineer. It will be apparent, even on a cursor" examination o f the following pages, that a handbook of mining must include a greater variety o f subject matter than books on other branches of engineering, and that* tfle field to be covered is too wide to be dealt with satisfactorily b y a single writer within* any reasonable period of time. In February and March, 1913, the Editor o f this book outlined the table of contents, and invited a number o f Associate Editors to contribute sections on their respective specialties. Besides those sections dealing with mineralogy, ore deposits, methods of prospecting, exploration and mining, and mining plant of all kinds, there are others on certain branches o f civil, electrical and mechanical engineering. I t m ay be thought by some that this collateral material occupies too much space in a book on mining. But, in view o f the important part played b y the allied branches o f engineering in equipping and operating m odem mines, the Editor believes the allotment of space is reasonable. He has endeavored to meet the demands not only o f engineers concerned with the devel opment and management of mines, but also of the large number of thc^e who have more to do with, and greater interest in, the construction details involved in. the installation o f plant. Therefore, the aim has been to supply such data on machinery, power plant, electric transmission and structural design, as the mining engineer m ay need when in the field and out o f reach o f his personal notes and technical library. For office use, there is at the end o f each section a bibliography o f the more important books and papers on the subjects dealt with. In practice, no well-defined boundary exists between the fields o f work of the mining engineer and the metallurgist. While, under some conditions and in some regions, the mining engineer’s functions end with the winning o f the ore and its delivery to a custom reduction works (mill or smelter), in other cases .the mining com pany’s plant includes a concentrating mill, amalgamating or cyaniding works (as at many gold and silver mines), or even a 3melting establishment, in planning the book, the question arose as to how much space should properly be given to the processes o f ore treatment. To cover any considerable part of the great field o f modem metallurgy would be imprac ticable, without extending the work beyond the limits o f a single volume. Realizing that the urgent need o f a companion Handbook o f Metallurgy must soon be supplied, it was decided, as a compromise, to furnish condensed summaries of those processes of treatment which are frequently carried on b y mining companies themselves. The book, therefore, contains sections on ore-dressing, ore-testing, gold amalgamation, an outline of the cyanide process, the preparation o f anthracite, bituminous coal and coke, and a brief r§sum§ o f certain facts respecting the selling, purchasing, and metallurgical treat ment of ores, that are of immediate interest to the engineer in control o f mining operations. The relatively small space allotted to coal mining is due chiefly to three considerations: first, a Coal-mining Pocketbook is already in existence; second, metal-mining methods
ix
PREFACE
X
are more varied than those for coal, due to the greater diversity in form and occurrence of metalliferous deposits; third, having discussed in Section 10, under Metal-mining Methods, the operations common to nearly all mining, the articles on coal mining are properly confined to the methods and data peculiar to that branch of the industry. The Question of supplying, cost data is difficult. A large number of itemized tables are included in the sections on Cost of Mining, Exploitation of Mineral Deposits, Boring, and other subjects, but costs of machines and apparatus are given sparingly throughout the book. This has been judged best, because of frequent price changes, and the great diversity of types of mechanical plant. In any case, to make close estimates, the engineer must apply to the makers for current prices. In some parts of the book, the names of machinery builders have been used freely, but without intention to indicate a preference for the product of any particular maker. While the Editor has aimed to make the style and arrangement uniform, he has had good reason to realize the difficulty o f securing consistency in these matters, considering the heterogeneous nature o f the subject matter, and the fact that it has been written or compiled b y so large a corps of Associate Editors. In these circumstances, unity and evenness o f treatment can hardly be expected, but an endeavor has been made to observe a reasonable proportion between the length of each section and its relative importance. T o save space, abbreviations are employed for a few words in common use by engineers, and chemical elements and compounds are generally represented b y their symbols. The thanks o f the Editor are due to members of the staff for their painstaking work, in many eases carried on in the intervals between pressing professional engagements in the field, and to the Publishers for their liberal spirit of cooperation in facilitating the preparation of the book. The Editor desires to express his especial appreciation of the valuable suggestions and assistance in revising manuscript and correcting proof, o f Professor Edward K . Judd, o f the Columbia School of Mines. It was planned to publish this book in 1916. The breaking out of the Great War, about one year after the work was begun, is responsible in large measure for the delay. R obebt P bble C olumbia. S chool op M in es ,
N ew Y o b x , December, 1917
LIST OF CONTRIBUTORS Arthur P. Ackerman.— Rock Excavation. Theodore Baumeister, Jr, Associate Professor of Mechanical Engineering, Columbia University; Consulting Engineer.— Power and Power Machinery. Clinton L. Bogert, Consulting Engineer.— Earth Excavation. Charles B. Breed, Professor o f Railway and Highway Engineering, Massachusetts Institute o f Technology.— Surveying. Philip B. Bucky, E .M ., Associate Professor of Mining, School o f Mines, Columbia University.— H oisting Plant, Shaft Pockets, and Ore Bins. C. H. Burnside, Late Associate Professor of Mechanics, Columbia University.— Engineers' Tables and Mathematics and M echanics. P. Ernest Brackett, Late Mining Engineer.— M ine Ventilation. Ralph H. Chambers, D .E ng., Consulting Civil Engineer.— Shaft Sinking in Unstable and Waterbearing Ground. H omer L. Carr, Mining Engineer.— Shaft Sinking in Rock. John A. Church, Jr., Mining Engineer.— Shaft Sinking in Rock. Walter M . Bake, Research Manager, Mining publications, M cGraw-Hill Publishing Company — Underground M echanical Loading, Conveying, and Handling. Richard T. Dana, C.E., Late Consulting Engineer.— Compressed A ir Practice, Earth Excavation and Rock Excavation. D. H. Davis, Chief Chemist, Pittsburgh Coal C o .— Preparation and Coking o f Bituminous Coal. John V. N . Dorr, Metallurgical Engineer, New Y ork City.— Gold Amalgamation and Cyanidaiion. Archibald Douglas o f Douglas & Armitage, Counsellors at Law, New York City. M ining Laws. Edward L. Dufourcq, Late Consulting Engineer.— Gold, Amalgamation and Cyanidatum. Edward B. Durham, Mining Engineer.— A erial Tramways and Cableways. Howard N. Eavenson, Mining Engineer.— Coke. J. K. Finch, Renwiek Professor of Civil Engineering, Columbia University.— Elements o f Hydraulics and Elements o f Structural Design. J. R . Finlay, Consulting Mining Engineer.— Coat o f M ining and M ine Organization and Accounts. Halbert P. Gillette, C .E .— Earth Excavation and Rock Excavation 's, J. Hall, Late ^Professor o f Assaying, School o f Mines, Columbia University. Aesayin'g. V. D . Hanson, Preparation Engineer, Pittsburgh Coal Co.— Preparation and Coking o f Bitum inous Coal. H . G. Haskell, E .M .— Explosives. Robert E. Hobart, Mechanical Superintendent, Lehigh Navigation Coal Go.— Drainage o f M ines. Edwin C. Holden, Consulting Mining Engineer.— Underground Transport. Fletcher B. Holmes, A.B.— Explosives. Charles F. Jackson, Mining Engineer.— Tunneling. Edwin S. Jarrett, C.E. (The Late).— Shaft Sinking in Unstable and Waterbearing Ground. Edward K. Judd, E .M ., Formerly Assistant Professor of Mining, School o f Mines, Columbia University.— Chemical and Physical Notes and Tables; Prospecting, Develop*
xii
LIST OF CONTRIBUTORS
ment and Exploitation o f M ineral D eposits; Underground Surveying; and Wages and W elfare. James Furman Kemp, Late Professor o f Geology, Columbia University.— Geology and M ineral D eposits. Edward F, Kc-rn, Formerly Professor of Metallurgy, School of Mines, Columbia Uni versity.— Assaying. Paul F. Kerr, Professor of Mineralogy, Columbia University.— Geology and M ineral D eposits and M ineralogy. Arthur LaMotte, Ph.G., B.Se.— Explosives. Frederick W . Lee, Chief, Section o f Geophysics, U S Geological Survey.— Geophysical Prospecting. F. J. LeMaistre, Ph.G., B.Sc.— Explosives. Robert S. Lewis, Professor o f Mining, University of Utah.— Boring. A. W . Loomis, Mechanical Engineer, Ingersoll-Rand Co.— Compressed A ir Practice. W . W . Lynch, E.M .— Prospecting, Development, and Exploitation o f M ineral D eposits. James F. McClelland, E .M ., Vice President, Phelps Dodge Corporation.— Prospecting, Development, and Exploitation o f M ineral D eposits and Engineers’ Tables. George E. McElroy, Senior M ining Engineer, U S Bureau o f Mines.— M ine Ventilation. Charles M . M eans, Consulting Engineer, Pittsburgh.— Electric Power for M ine Service. Alfred J. M oses, Late Professor o f Mineralogy, Columbia University.— Mineralogy. Arthur Rotman, Consulting Engineer.— Cost o f M ining and M ine Organization and Accounts. Robert Van Arsdale Norris, Late Consulting Mining Engineer.— Drainage o f M ines. S. M . Parade;, Preparation Engineer, Pittsburgh Coal Co.— Preparation and Coking o f Bituminous Coal. EC. L. Parr, Professor of Mechanical Engineering, Columbia University.— Mechanical Engineering M iscellany. Robert Peele, Professor Emeritus o f Mining Engineering, School of Mines, Columbia University.— Chemical and Physical N otes and Tables and Engineers’ Tables. George S. Rice, Formerly Chief Mining Engineer, U S Bureau o f Mines.— M in e A ir, Gases, Dusts, H ygiene, Explosions, and Accidents. Samuel R . Russell, Explosives D ept, E. I. D uPont de Nemours & Co.— Rock Excar* nation. Reno H . Sales, Geologist to the Anaconda Copper Mining € o , Butte, M ont.— M ine Geologic M aps and Models. Walter I. Slichtef, Professor o f Electrical Engineering, Columbia University.— Electrical Engineering. S. F. Shaw, E .M ., Consulting Engineer, Westgate OE C o, Anglo-Canadian Oil Co, Ltd, etc .— Petroleum Production Methods. Paul Sterling, Mechanical Engineer, Lehigh Valley Coal Co.— Preparation and Storage o f Anthracite Coal. Arthur F. Taggart, Professor o f M in e rs Dressing, School o f Mines, Columbia University.— Boring; Breaking, Crushing, and Sorting o f Ores; and Testing o f Ores. Edward D . Thurston, Jr, Formerly Associate Professor of Mechanical Engineering, Columbia University.— Engineering Thermodynamics. Arthur L. Walker, Formerly Professor of Metallurgy, School o f Mines, Columbia University.— Selling, Purchasing, and Treatment o f Ores. William M . Weigel, E .M .— H oisting Plant, Shaft Pockets, and Ore Bins. William Young Westervelt, Consulting Mining Engineer.— M ine Examinations, Valuations, and Reports. Horace V. Winchell, Late o f the California Bar.— M ining Laws. George R. W ood, Electrical Engineer.— Electric Power fo r M ine Service. T. R. Woodbridge, Late Consulting Metallurgical Chemist, U S Bureau o f Mines.— Ore Sampling,
TABLE OF CONTENTS FOR VOLUME I Detailed tables of contents are given at the beginning of each section. appears following Section 14. SECTION 1.
An alphabetical index
SECTION 9. BORING
MINERALOGY PÀ.QE
Identification of Minerals................... 02- 10 Occurrence and Association of Min erals.. .......................................... .. 10- 11 Uses and Products of Minerals........... 12- 14 Descriptive and Determinative Tables. 16- 52 SECTION 2. GEOLOGY AND MINERAL DEPOSITS Geology: Hocks, Composition and • Occurrence........................................ 02— 17 Mineral Deposits, Metalliferous......... 18- 27 Mineral Deposits, Non-metallia.......... 2 8- 32 SECTION S. EARTH EXCAVATION , Economics, Physics, Mechanics.......... 02- 04 Excavating Equipment and Methods. 06- 17 Embankments and Dams............... 18 t SECTION 4. EXPLOSIVES Chemistry and Composition............... 02- 09 Transport, Storage, Handling............. 10- 18 Charging and Firing; Blasting Sup plies......................................... 19— 31 SECTION 8 . ROCK EXCAVATION Rock Characteristics........................... ...02Drill Bite; Hand and Machine Drilling. 03Blasting; Charging and Firing...............11Loading by Hand and Machine.............21Quarrying; Open-cutting; Trenching,. 23SECTION 6. TUNNELING Examples and Organization................ Plant and Equipment......................... Drilling, Blasting, Mucking, Tram ming .............. .............................. Ventilating, Timbering; Work in Loose Ground................................... Costs.....................................................
03 11 21 23 28
02- 06 06- 08 08—20 20- 26 2 6 -2 8
SECTION 7. SHAFT SINKING IN ROCK Shape and Size of Shafts..................... 02Plant and Organisation....................... 03Thrilling, Blasting, Mucking, Ventilat ing.......................... ......................... 06Working Shafts; Raising of Shafts.,. . 11Wall Support: Timber, Steel, Con crete, Etc.......................................... 12Kind-Chaudron Method..................... 22Speed and Costs.................................. 23-
03 06 11
12 22 23 32
SECTION 8 . SHAFT SINKING IN UNSTABLE AND WATERBEARING GROUND Expedients; Piling........................... ‘ . 02- 08 Drop-shafts; Pneumatio; Honigmann. 06- 20 Freezing; Cementation and Grouting. 20- 24
Shallow Work: Augers, Spring-pole, Empire Drill, Etc............................. Oil-well Drilling, Casing, Sampling; Directional Drilling; Costa.............. Churn Drilling for Prospecting; for Blasting............................................ Diamond-drilling Equipment, Meth ods, Costa......................................... Shot or Calyx Drilling......................... Surveying of Boreholes; Choice of Boring Method................................
PASS 02- 09 09- 40 4 1 -4 4 44- 61 61- 63 63- 69
SECTION 10. PROSPECTING, DEVELOPMENT, AND EXPLOITATION OF MINERAL DEPOSITS Definitions; Surface Prospecting........ 02- 33 Exploration by Boring; Sampling and Estimating........................................ 34- 75 Exploration by Shafts, Tunnels, Etc; Equipment....................................... 7 6- 80 Development: Entry, Drifts and Cross cuts, Raises, Winzes......................... 81-123 Exploitation: Classification of Meth ods; Breaking Ground..................... 123—132 Open Stopes: Gophering, Breasting, Room-and-pillar, Under- and Over hand, Sub-level Methods................. 132—197 Squaie-set Stoping; Mitchell and other Systems; Timber Preservation 197-236 Filled Stopes, Horizontal, Inclined; Resuing; Crosscut Method............. 237-274 Shrinkage Stopes.................- .............. 274-297 Caving Methods: Top-ahcing; Sublevel Caving; Bioek-caving............. 297-371 Combined Methods: Boston Con, Ray, Miami, DeBeers, E tc............. 371-398 Mining through Boreholes; Leaching Ore in Place; Chutes and Gates; Mechanical Handling; Sand Filling; Choice of Mining Method........... 398-438 Open-cut Mining, Hand- and Machine loading; Glory-holing; Coal Strip ping. .............................................. .. 430-472 Coal Mining: Room-and-pillar; Rob bing Pillars; Longwali..................... 472-619 Ground Movement and Subsidence... 519-533 Placer and Hydraulic Mining; Sluices and Riffles; Elevators; Dredges and Dredging; Drift Mining; Thawing.. 533-619 Mining Alluvial Tin in Malaya.......... 619-629 SECTION 10-A. GEOPHYSICAL PROSPECTING Gravimetric, Magnetic, and Electrical Methods.................................. . 02— 21 Seismic Prospecting............................. 21- 26 Temperature, Radioactivity, and Micro-gas Surveys; Choice of Method............................................. 26- 29
xiii
xiv
TABLE OF CONTENTS PAGE
Physical Properties of Rocks and Min erals. ................................................
^
SECTION 11. UNDERGROUND TRANSPORT General Considerations; Primitive Methods...............................................02- 03 Mino Cars, Track, Dumps.....................03- 32 Tramming; Animal Haulage... 3 2 -3 5 Locomotive Haulage........................... ...35- 41 Rope and Miscellaneous Haulage; Costs; Accidents.............................. ...41— 46 SECTION 12. HOISTING PLANT, SHAFT POCKETS, AND ORE BINS Hoisting Systems; Drums, Brakes and Clutches; Sheaves............................ ‘ 02- 18 Hoisting Ropes: Vegetable-fiber; Wire 19- 29 Hoisting Cycles: Cylindrical, Conical, Cylindro-conical Drums................... 29—40 Hoists, Types and Calculations; Elec tric, Steam, Comp-air, E tc.............. 42- 56 Windlass and whim................. ........... 57— 58 ffniating in Deep Shafts; Examples 58— 60 and Costs.............................. Headframes: Designs in Wood, Steel, anii Concrete.................................... 61" 82
PAGE
Guides and Tracks; Signal Systems... Buckets, Cages, Skips: Design and Construction; Overwinding-----'----Shaft Pockets...................................... Ore Bins: Design and Construction.. .
82- 91 91-119 119-125 126-135
SECTION 1
SECTION 13. DRAINAGE OF MINES Sources and Control of Mine Water; Prevention....................................... 02- 04 Sumps, Dams, Tunnels, Siphons; Hoisting of Water............................ 04- 11 Mine Pumps: Steam, Comp-air, Air lift, Electric...................................... 11— 21
MINERALOGY BY A L F R E D J. M O SES
SECTION 14. MINE VENTILATION Mine Atmosphere; Ventilating Sys tems .................................................. 02— 07 Air Distribution; Velocity and Control 07— 14 Auxiliary Ventilation; Leakage; Effect of Mining Method........................... 14- 21 Measurements; Air Flow; Mine Re sistance............................................. 21—34 Ventilating Methods and Equipment: Natural; Mechanical....................... 34- 44 Mine Fans: Characteristics, Applica tions, Selection................................. 44- 54 Cooling and Air Conditioning............. 54- 64
T.ATT! PR O F E SS O R O F M IN E R A L O G Y , CO LU M BIA U N lV B E S il't R E V IS E D B Y
PAU L F. K EU U P R O F E SS O R O F M IN E R A L O G Y , C O LU M BIA U N IV E R S IT Y
PAGE
AST
For contents of other handbooks o f this series, see pages following Index of this volume.
DESCRIPTIVE AND DETERMINATIVE TABLES General Division
IDENTIFICATION AND STUDY OF MINERALS 1. Definitions.......................................
2 . Identification by Aid of Crystals. . 3. Important Physical Tests not Directly Dependent on Crystalline Structure 4. Testing with the Blowpipe................. 5. X-ray Methods of Study.................. Polished Surfaces of Metallic Ores. . . Examination of Fragments of Non • opaque Minerals.......................... Examination of Thin Sections.......
GBOUP
2
6
7 9 9 10
10
OCCURRENCE AND ASSOCIATION OF MINERALS 9. 10. 11. 12.
Minerals of Rocks and Veins........* .. 10 Minerals of Saline Residues................. ... 11 Minerals of Gravels, Clays, and Marls 11 Contact Minerals.................................. ... 11 USES OF MINERALS
13. Uses of Minerals in their Natural State 14. Products Extracted or Manufactured from Minerals....................................
12
12
. .
.
1 2J Minerals of Metallic .or Sub-metallic n.Luster, Black or Nearly Black in '■'Color.............................................. 3 4. Minerals of Metallio Luster, Tm White. Silver White, Lead-Gray or Steel-Gray in Color........................... 5, 6 . Minerals of Metallic Luster, Metallic Yellow, Bronze or Red in Color----7, 8 , 9,10. Minerals of Non-metallio Lus ter, with Decided Taste................... 11,12,13,14,15. Minerals of Non-metallio Luster, Tasteless, with Colored Streak............................................... 16,17,18. Minerals of Non-metallic Lus ter, Tasteless, with White Streak, Yielding Reactions on Charcoal with Sodic Carbonate................................ 19,20, 21, 22, 23, 24. Minerals of Non-me tallic Luster, Tasteless, with White Streak, Yielding no Tests with Sodic Carbonate...................................... 25. Mineral Substances not Easily Deter minable by a Scheme....................... Index to Determinative Tables.......... Bibliography.........................................
1-01
16 21 24 25 27
32
36 50 51 63
IDENTIFICATION BY AID OF CRYSTALS
1-03
Divisions or “ systems ” based oa symmetry. T he following seven divisions result readily from this partial determination of symmetry, the statements not implying the absence of other symmetry elements: 1. Isometric............... 2. Tetragonal............. 3. Hexagonal.............
IDENTIFICATION AND STUDY OF MINERALS
4. Hexagonal.............
1. DEFINITIONS
5. Orthorhombic. . . .
On the basis of several thousand analyses the crust of the earth for a depth o f about ten miles is estimated b y Clarke, “ Data o f Geochemistry,” to be composed almost entirely o f compounds o f fourteen elements:
7. Triclinic.................
Per cent
Per cent
Per cent
49.78 26.08 7.34 4.11 3.19
2.33 2.28 2.24 0.95 0.37
0.21
0.19 0.11 0.11
Total____ :...............
99.29
These great elements, and the sixty or so others which form the remaining fraction of 1 % , occur in approximately 1500 different chemical combinations, known as minerals; that is, as homogeneous substances o f definite chemical com position, found ready-made in nature, and not directly a product o f the life or decay o f an organism. The two conditions in which minerals may occur. A mineral, like other chemical substances, usually occurs either in crystals of characteristic shapes or in m a s s » made up o f many crystals so crowded together that the shapes are not evident, although in each grain of the aggregation the crystalline structure will be shown b y the constancy o f the properties in parallel directions and their variation in directions n ot parallel. Any mineral m ay in solidifying fail to assume a crystalline structure, because o f too great viscosity, or too rapid cooling, or other cause. I f this condition is invariable, the mineral is said to be amorphous. Opal is the best example. Amorphous minerals are few in number.
2. IDENTIFICATION BY AID OF CRYSTALS T he forms o f crystals are often a great aid in mineral identification- Symmetry, interfacial angles a id crystal habit are also o f value. Cleavage an&markings on crystal faces axe significant. ' Symmetry. In every complete crystal there is some repetition o f angles and similarly grouped faces. B y considering this so-called “ symmetry ” crystals m ay be grouped in divisions, and as all crystals of any one mineral have the same grade o f “ symmetry,” they belong to the same symmetry division. In identifying an »Tia o f symmetry imagine or actually cause the crystal to revolve about some prominent line through its centre. Note the groupings o f faces at the initial position. N ote whether at any stage o f the revolution the crystal faces appear to be ail coincident (rarely), or all parallel to the initial positions of other faces. Or, in other words, note whether groups o f faces are replaced during the revolution b y other groups containing just as many faces at exactly the angles o f the first set. If so, a probable axis o f symmetry has been determined. I f b y measurement the angles o f one set correspond in value and order with those of the other sets, then the existence o f the symmetry axis is confirmed. According to the number .of times corresponding groups or faces recur during a complete revolution about a symmetry axis the axis is known as two-fold, three-fold, four-fold, or six-fold. These are the ordinary axes o f symmetry. I f a plane so divides the crystal that on each side of that plane there are grouped the same number o f faces at the same angles to it and to each other, this plane is called a Plane o f Symmetry.
1— 02
6 . M onoclinic.............
/ More than one axis o f three-fold symmetry. (Often also more \ than one o f four-fold.) One axis of four-fold symmetry and one only. / Rhombohedral division— one axis of three-fold symmetry and \ one only. Hexagonal division— one axis o f six-fold syinmetry. Three axes of two-fold symmetry, but nothing higher than two fold; or one axis of two-fold symmetry at the intersection of two planes of symmetry. / One axis o f two-fold symmetry and one only, or one plane of \ symmetry, or both. Without axes or planes o f symmetry.
Distinguishing species by angles. Although different crystals o f the same substance may differ-in shape, angles, and number o f faces, the angles between corresponding faces are constant and characteristic. Corresponding faces on the same crystal, or on different crystals o f the same substance, occupy corresponding or analogous positions with reference to the symmetry axes and usually correspond in lustre and markings. . They frequently do not correspond in shape. The measuring of a few selected angles will, therefore, usually serve to differentiate the crystal from others in the same symmetry division. Angles may be determined within one or two degrees by a very simple apparatus, such as the Penfield No. 2 goniometer, consisting of a cardboard <5n which is printed a graduated semicircle, with an arm of celluloid swiveled by an eyelet in the centre of the semicircle, or better a similar apparatus of metal with removable and adjustable arms. In using, the crystal is placed so that the card edge and, the swinging arm, or the two metal arms, are each in contact with a face and perpen dicular to the edge of intersection of the two faces, and the mean of at least three readings is used. The “ cleavage” directions, obtained as described later, are of great service in orientating the crystal. These and the angles between them are used in the lists which follow each system. Zones are composed of faces all parallel to the same line. Their intersections are therefore parallel to this line and to each other. — Isometric crystals. I f a crystal shows m ore.than one axis of three-fold symmetry it is an isometric crystal, and n ot otherwise. There will always be present, also, axes of two-fold or four-fold symmetry. The faces are often squares and equilateral triangles, or these modified b y cutting off corners. The dimensions are usually approximately equal in several directions, the forms approaching sometimes to the sphere. Repetitions in any crystal o f equal angles and “ corresponding ” faces are more frequent than in other crystal systems. Angles. These are of the same series whatever the species. The important species may be classed by their “ habit” ; that is, the dominant forms of the crystals, as follows: Tetrahedral. (Tetrahedron angles, 70° 310 boracite, sphalerite, tetrahedrite. Cubic. With easy cubic cleavage: cobaltite, galena, halite; with octahedral cleavage: fluorite, smaltite; without marked cleavage: argentite, boracite, cerargyrite, cuprite, pyrite. Octahedral. (Octahedron angles, 109® 29') chromite, cobaltite, cuprite, fluorite, frank]mite, galena, gold, linnseite, magnetite, pyrite, spinel. Cleavages: galena, cubic; fluorite, octahedral. Partings: franklinite and magnetite, octahedral. Dodecahedral. (Dodecahedron angles, 120°) boracite, cuprite, garnet, magnetite, sphalerite. Trapezohedral. (24-faced trapezohedra, approximating spheres; common angles, 131° Id', 146° 270 analcite, garnet, leucite. Pyritohedral. (12-faced pyritohedra; most common angles, 126° 53' and 113® 350 cobaltite, pyrite, smaltite. Tetragonal crystals. I f the crystal shows one axis of four-fold symmetry, and only one, it is a tetragonal crystal, and n ot otherwise. A section taken at right angles to the four-fold axis is usually square or octagonal, or more rarely the angles are again truncated. The dimension in direction o f the.four-fold axis is usually notably greater or less than in directions at right angles thereto. Angles, la the zone of faces parallel to the four-fold axis there are no variations in angle dependent on the species. Between prominent corresponding faces the angles are almost always
1-04
IDENTIFICATION BY AID OF CRYSTALS
MINERALOGY
90°, and between prominent adjacent faces either 90° or 135°. The characterizing angles lie in other zones. , , , ... , . The principal tetragonal minerals may be classified by angles and cleavage as foilowss Angtes between corresponding faces oblique to ike four-fold axis: chalcopyrite, 71° 20'; wulfemte, 99 38 ; scheelite, 100° 5'; apophyllite, 105°; braunite, 109° 53'; cassitente, 121° 41'; rutile, 123 8 ; zircon, 123° 19'; vesuvianite, 129° 21'; wernerite, 136° 15'. _ Braunite» scheelite, and wuifenite cleave at the angles mentioned. Wernerite and rutile cleave parallel to the four-fold axis, giving angles of 90° and 135°. Apophyllite cleaves at right angles to the four-fold axis. Hexagonal crystals. If the crystal shows one and only one axis of three-fold symmetry it is a hexagonal crystal, rhombohedrai division. I f the crystal^ shows one and only one gyjg 0f six-fold symmetry it is a hexagonal crystal, hexagonal division. A section taken at right angles to the axis o f three-fold or six-fold symmetry is usually a hexagon, or its most prominent edges form a hexagon or at least an equiangular triangle. N ot infre quently each angle is replaced b y one or two smaller edges. The dim ension parallel to this nvig ja usually notably greater or less than the dimensions at right angles thereto. Angles. In the zone of faces parallel to the three-fold (or six-fold) axis there are no variations in angle dependent on the species. The angles between prominent corresponding faces are chiefly 120° or 60°. Other angles in this zone are usually large and their occurrence leads to an apparently rounded, often nearly circular, cross-section. •The characterizing angles lie in other zones. The crystals of important hexagonal minerals may be classified by angles between corresponding faces and by cleavage as follows: L With evident axis of three-fold symmetry and usually rhombohedrai habit: Angles which are both interfacial and between cleavage directions. Soda nitre, 73° 30'; chabazite, 85° 14'; hematite, 86 °; calcite, 105° V ; dolomite, 106° 15'; rhodochrosite, 107°; adente, 107®; magnesite, 107® 24'; smithsonite, 107° 40'; proustite, 107° 58'. Angles which are interfacial only. Umenite, 85° 31'; alunite, 90° SO'; cinnabar, 92° 37'; willemite, 115° 30'; phenacite, 116° 36'; tourmaline, 133° 8' or 103°. , H. With real or apparent of six-fold symmetry, and usually prismatic habit: Prisms capped by faces oblique to axis and at angles, for example, corundum, 86 4' or 128 2 ; quartz, 94° 14' or 133° 44'; apatite, 142° 15'. . ... . Prisms usually capped by single face at right angles to axis. Beryl, lodynte, mimetite, nephelite, pyrargyrite, pyromorphite, vanadinite. Tabular. Graphite, molybdenite, iridosmine. Orthorhombic crystals. If a crystal shows either three axes of two-fold symmetry or one axis with two planes of symmetry, and nothing o f higher symmetry, it belongs to the orthorhombic system. Cross-sections taken at right angles to the axes o f symmetry are in angles, and tend to rectangles and rhombs or to these combined. Angles. There is no zone of faces which has a constant series of angles for all species. The interfacial angles in the zones parallel to the axes of symmetry are unlike (except when 90°) and vary with the species. The orientation is brat obtained by reference to cleavages, and on this basis the important species may be tabulated as follows: L With one direction of cleavage which bisects prominent angles, for example: stibnite, 90° 26'; sillimamte, 91° 45'; goethite, 94® 52'; manganite, 99® 40'; brochantite, 104® 32'; atacamite, 113® 03'; staurolite, 129® 20/. Topaz, with one direction of cleavage, has prominent angles 124° 17' and 90® 11', not bisected by the cleavage. n Crystals with two directions of cleavage or more than two in one zone, and common angles between faces parallel to two such directions? columbite and olivine, 90°; andalusite, 90° 48'; nafcrolite 91° 15'- enargite, 97° 53'; hemimorphite, 103° 51'; araenopynte, 112® 27'; cerussite, 117a 14'; strontianite, 117° 19'; aragonite, 118® 12'; chalcoeite, 119® 35'. m Crvstals with three or more directions of cleavage not in one zone, and common angles between faces parallel to such directions: anhydrite, 90®; barite 90° and 101® 38'; angledte, 90® e l d 1<^® 44'Tcelestite, 90® and 104® 10'; stephanite, 90® and 107° 44'. Monoclinic crystals. If a crystal shows one and only one axis o f two-fold symmetry, or one and only one plane of symmetry, or both, it is a monoclinic crystal. A ny face in the zone of the symmetry axis makes a 90® angle with the symmetry plane (or a face parallel to it). N o other 90° angles occur. The cross-section of the zone of the symmetry axis is never rectangular, rarely rhombic and usually markedly unsymmetricaL Anglftg. No zone has a constant series of angles for each species. In this system the one symmetry plane, the one symmetry a m and the cleavages, all assist in the orientation leading to the following tabulation:
Easiest cleavage
Angles in zone of symmetry axis
Species
no® 9% in® w Parallel to symmetry
M l 8° 6', 124® 18' I 117°
Perpendicular to sym-
( 135° 14', 137° 10', t 132° 45' 106° 35' 124® 58', 124° 43' Epidote........................ f 115® 23', 128® 19', X 155° 11' ( 140® 48', 87® 17', t 126° 29' 99° 42', 129® 44' Orthoclase.................... 90® 130° 6'
Angle between easiest cleavages bisected by plane of symmetry..'
105° 50', 148® 40' Spodumene..................
no® 20' 140® 4y, 159° * \ . 90° 9“! 135°
1~05
Angles bisected by symmetry plane 1 107° 56', 140® 12', ( 126® 9' f 131° 30', 143® 48', { 138® 40' 74® 26', 132® y 108® 2' 100® 37', 98° 6', 117° 49' 99° 19', 119° 13', 90° 53' 87®, 122° 33', 96® 32' 91® 58', 71® 32' 70° 4', 70® 29', 63° 5' 93® 26' 118° 47', 90° 7' 119° 58' 124° II', 148® 28' 93® 41', 119® 10' (87° 10', 120° 49’, I 331® 31' 87°, 91° 26 ( 113® 31', 136® M', I 67® 57' i l l 5 ° W , 120° 56', t 1)5® 21
The micas and chlorites are usually pseudo-hexagonal. Triclinic crystals. I f the crystal shows no axes nor planes of symmetry it is a triclinic crystal. There will be no right angles either between faces or edg&s. The only correspond ing faces will be opposite (parallel) faees. The crystals of some o f the m ost prominent triclinic minerals, however, approximate in angles monoclinic crystals but are usually b y the occurrence o f faces which have no symmetrically placed associates. Anglea No angle will occur more than twice in any crystal. There are comparatively few common triclinic species. The following table records a few of their most important angles. Angles between the two easiest cleavages or the faces parallel to the cleavages The Plagioclases: .............
94® 10'
Other angles between common adjacent faces 127° 44', 120° 46' 116° 3', 98° 46', 120® 31' 128° 3', 98® 8', 120® 54'
Cleavage and its value as a test. In any crystal, whether with characteristic external form or not, the cohesion varies in different directions. Under strain there is frequently a tendency to split or cleave perpendicular to the d ire ctio n s^ weakest cohesion in definite planes, which are always parallel to possible faces o f simple crystals characteristic of the substance. All crystals ‘of the same substance yield like cleavages. The number of directions o f cleavage and the angles between the cleavage planes are characteristic; more over the cleavages serve to orientate the crystals in many cases. I f the individual crystals are large enough, cleavage is obtained b y placing the edge o f a knife or chisel upon the crystal and striking it a sharp, quick blow. I f the individual crystals are very small the cleavage directions can usually be developed b y crushing with pressure or a blow, and examining the fragments with a hand glass. In pyrotene, spodumene, corundum, mag netite, and some other species, some specimens break easily in definite planes, while other*
MINERALOGY
TESTING WITH THE BLOWPIPE
do not. This is n ot true cleavage, but a secondary phenomenon due to pressure, and is called “ parting.” Cleavage and parting shapes m ay be microscopically determined. T o do this, sieve the crushed material through a 100-mesh screen upon a 120-mesh screen. Crushed frag ments of transparent minerals m ay be placed on a slide, covered with a transparent liquid, and examined b y the pétrographie microscope, as described b y E. S. Larsen and H. Berman, ÜSGS, B vll. 848 (1934) (Bib). Thin sections of massive, transparent minerals or rocks m ay be examined as described in T hinsection M ineralogy, b y A. F. Rogers and P. P. Kerr, McGraw-Hill, N Y , 1933.
Special specific-gravity balance. An improved form, suitable for non-porous solids, has been described by Kerr. It is useful for rapid and accurate determinations. Though based upon the usual chemical balance, it has a notched beam with rollers for weighing. Heavy liquids. If a fragment of a mineral is floating in a liquid of higher specific gravity and a diluent is stirred in, drop by drop, until the fragment if pushed down will neither sink nor rise but stay where pushed, the specific gravity of the liquid as determined by a Westphal balance will be the specific gravity of the mineral. The heavy liquids moat used are: clerici solution, a mixture of thallium malonate and thallium formate (4.25), diluent, water; methylene iodide (3.32), diluent, benzol; bromoform (2.90), diluent, xylol or benzol; solution of mercuric iodide and potassie iodide (3.2), diluent, water.
1 -0 6
3. IMPORTANT PHYSICAL TESTS NOT DIRECTLY DEPENDENT ON CRYSTALLINE STRUCTURE The most important o f these tests or characters are Luster, Color and Streak, Hard ness, and Specific Gravity. Lustre. The luster of a mineral is dependent upon its refractive power, its transparency, and its structure. I t may be called the kind o f brilliancy or shine o f the mineral. In determinative work minerals are broadly divided into Metallic and Non-metallic. Metallic luster is the luster o f metals. It is exhibited only b y opaque minerals, and these, with the exception o f the native metals, have a black or nearly black streak. Opaque darkcolored minerals not distinctly non-metallic are said to be sub-metallic. Non-metallic luster is exhibited b y all transparent or translucent minerals. It m ay be vitreous or glassy, adamantine like the cut diamond, resinous like sphalerite, pearly like mother of pearl, silky like fibrous serpentine, greasy like nephelite, or waxy like chalcedony. Hardness. The resistance o f a smooth plane surface to abrasion is called its hardness and is recorded in terms o f the following scale : 6 .0 Orthodase 1 .0 Talc 8 .5 Chrysoberyl 7 .0 Quartz 2 .0 Gypsum 9 .0 Sapphire 7 .5 Zircon 3 .0 Calcite 9 .5 Carborundum 4 .0 Fluorite 8 .0 Topaz 1 0 .0 Diamond 5 .0 Apatite Approximations may be reached b y use o f finger nail (2 1 / 2), copper coin (3) and knife ( 5 112). Some smooth surface o f the mineral to be tested is selected, on which a point of the standard is pressed and m oved back and forth several times one-eighth o f an inch or less. If the mineral is scratched it is softer than the standard. Tw o minerals o f equal ho.rdnp.afi will scratch each other. Pulverulent or splintery minerals are “ broken down ” b y the test and yield an “ apparent ” hardness often much lower than the true hardness. Rough surfaces also yield doubtful results. Color and streak. The color o f minerals of metallic luster and the color o f the powder, or streak, when n ot white, are very much used in sight recognition. Minerals with nonmetallic luster often vary greatly in color. The color is most safely obtained on a fresh surface. The streak is usually obtained b y rubbing the mineral on a smooth but not glazed white or black surface, such as a porcelain “ streak plate ” or a piece of touchstone (black quartz). The excess o f powder should be brushed away and the thin adhering layer considered. Specific gravity. The specific gravity o f a substance is equal to its weight divided b y the weight of an equal volume o f distilled water at 4 ° C. Ordinarily room temperature is used. Pure com pact material is needed. The most accurate results are obtained b y a delicate chemical balance, but for determinative purposes the following are more rapid and sufficiently accurate. The Jolly balance. Two scale pans are attached, oae below the other, to a spiral spring, parallel to which is a mirror with a graduated scale. The lower scale pan is kept submerged in distilled water. The coincidence of a bead on the wire and its image in the mirror give: A = Heading with nothing in either scale pan. B = “ “ mineral in upper scale pan. C= H « same fragment in lower scale pan. Sp Gr = CB - A) + (B - O The Westphal balance; More accurate results are obtained by substituting for the thermometer float of a Westphal balance a double scale pan, the lower pan of which must be immersed in distilled water. A = Weight needed to balance apparatus. B =» “ “ “ “ “ with mineral ia upper scale pan. C <= “ “ “ “ “ “ “ “ lower scale pan; Sp Gr <=• (A - B) * (C - B)
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4. TESTING WITH THE BLOWPIPE Apparatus.
The essential pieces o f apparatus for all the tests given are:
1. Either a gas blowpipe, or some form of burner for gas or heavy oil and a plain blowpipe. 2. Platinum wire about 0.25 mm diameter. Six inches of it will make four wires. A holder is needed. 3. Platinum-pointed forceps. 4. Charcoal in convenient sizes and with smooth surfaces (say 4 b y 1 b y 5/s in). 6 . Tubes of hard glass about 3 b y 3/l6 in, closed at one en d 6 . Pocket lens o f good quality, 7. Simple goniometer. 8 . Merwin Color Screen (G. M . Flint, Cambridge, Mass). Por the other apparatus considerable latitude is possible and substitutes can be impro vised for the regular stock article. The needed list would be: watch glasses, bottles (I oz) for reagents, hammer, anvil, and magnet. s A bout ten reagents are used, the principal beingsborax, salt o f phosphorus, sodic car bonate, potassie bisulphate, cobaltic nitrate, and ‘¡hydrochloric acid. Tw o others are needed in preparing the bismuth flux and there will be needed occasionally metallic tin and nitric or sulphuric acid. A continuous blowpipe blast is obtained b y distending the cheeks and using the mouth as an air reservoir, breathing regularly through the nose and from time to time admitting more air from the lungs through the throat to the mouth. A ny luminous flame may be used and, b y regulating the relative amounts of air and flame, may be “ blown " a s a clear blue flame or a yellow flame, both o f which owe their color to incomplete combustion (CO or C) and therefore tend to reduce, that is, to take oxygen from substances placed therein. Hereafter this fíame is designated b y the letters R.P. A practically non-luminous colorless envelope surrounds the blue flame and less distinctly the yellow flame. In this there is an excess o f oxygen and it' therefore tends to oxidize substances placed therein. Hereafter this flame is designated b y the letters O.F. Fusion or fusibility. The ease o f fusibility and the phenomena during fusion are con venient tests. The hottest portion o f the flame is just beyond the tip o f the blue flame. Some substances, noticeably certain iron orea, which are infusible in the oxidizing flame are fusible in the reducing flame. .. The test is most safely made b y first heating on charcoal a fragment o f the substance the size of a pin’ s head, to prove presence or absence o f volatile or easily-reducible elemente, which are likely to alloy with platinum. I f these are present the fusion test must be limited to the test on charcoal. I f reducible metals or volatile constituents axe absent, a small sharp-edged fragment is heated in-the platinum forceps, a t the tip o f the blue flame, directing the flame upon the point. Fragments long enough to project beyond the platinum should be used and it is always well to examine the splinter with a magnifying glass, before and after heating. Fragments fo r comparison must be approximately o f same size and shape. The degree of fusibility is stated either in terms of a scale of fusibility, suggested by vos KobeD, or more simply as easily fusible, fusible, fusible with difficulty, or infusible: Easily fusible’ Í coarse splinters fuse in a candle flame. ' (2 . Ckalcopyrite, small fragmento fuse in the Bunsen burner flame. f3. Garnet (almandüe), coarse splinters easily fuse before the blowpipe. Fusible: | Not fusible in Bunsen burner. 14. Áctinclüe, fine splinters fuse easily before the blowpipe, f 5. Orthodase, fused only in fine splinters or on thin edges before the Fusible with difficulty: j blowpipe. 16. Hemimorphite, finest edge only rounded in hottest part of fiame. Infusible: 7. Quartz, infusible, retaining the edge is all its sharpness.
1-09
MINERALOGY
POLISHED SURFACES OF METALLIC ORES
The result of the fusion may be a glass or slag, which is clear and transparent, or white and opaque, or of some color, or filled with bubbles; during the fusion there may be a frothing or intu mescence, or a swelling and splitting (exfoliation). In certain instances the color and form may ehange without fusion, or the substance may take fire and burn, or fusion may follow the loss of some volatile constituent.
Vol 30, p 571), consisting of three colored strips of celluloid; N o. 1, blue. No. 2; over lapping blue and violet, No. 3, violet. These absorb different portions of the spectrum as follows:
1 -0 8
Solubility. Acids, especially dilute (1 : 1) hydrochloric acid, are used not only to deter mine composition but also to determine the ease or degree of solubility. This test fails only from carelessness. The substance must be selected as nearly pure as possible, finely ground added to the acid in successive small quantities. A clear solution should be aimed at, acid being added if more is needed until everything has dissolved. If complete solution cannot be obtained, the liquid must be filtered and the clear filtrate slowly and partially evaporated until separation commences. If doubt exists as to solubility the liquid must be evaporated to dryness, a residue proving solution to have taken place. Solu bility may be accompanied b y effervescence with or without odor in cold acid, or only on heating. The evaporation may be difficult and incomplete, or there m ay be separation of a perfect jelly, or of separate lumps of jelly, or of powder, or of crystals. The solution may be of a characteristic color. Testing for chemical components. The tests used are described in place in the deter minative tables following A rt 14. The manipulations and precautions axe briefly as foEows: L Testing in closed tubes. A narrow tube of hard glass, about 3 m by_ 3 /i 8 m and closed at one end, is best. Enough o f the substance is slid down a narrow strip o f paper, previously inserted in the tube, to fill it to the height of about in» the paper is with drawn, and the inclined tube heated gradually at the lower end to a red heat. Soda or other reagents are sometimes mixed with the substance. The results may be: evolution of water, odorous or non-odorous vapors, sublimates of various colors, decrepitation, phosphorescence, fusion, charring, change o f coior, and magnetization. n . Testing on charcoal. A shallow cavity, to prevent the substance from slipping, is bored at one end of the charcoal, and a small fragment o f the mineral is placed in it. The charcoal is held in the left hand, the surface tipped at about 120 ° to the direction in which the flame is blown, and a gentle O.F. is blown on the substance. If no sublimate forms the heat is increased, still keeping the flame oxidizing. Another fragment is tested in the R .F ., the substance being kept covered for several minutes with the yellow flame. The sublimates, their color, position on the charcoal, ease of removal b y heating in the O.F. or R .F ., and the colors'imparted to the flame are all noted. Chemical changes may also be indicated b y reduced metal, magnetic residues, alkalinity, etc. . m . Testing with soda on charcoal. Sodic carbonate (“ S od a ” ), heated on char coal, acts as a flux; it also exerts a reducing action, attributed to the formation of sodio cyanide, nascent sodium, and carbon monoxide. It combines with many substances, forming both fusible and infusible compounds. The m ost satisfactory general method is to mix one part o f the substance to be tested with three parte of moistened soda and a little borax, and treat with a good R .F . on charcoal until everything that can be absorbed has disappeared. IV. Testing with bismuth flux on charcoal and on plaster tablets. Sublimates of brilliantly colored iodides and sulpho-iodides axe obtained if bismuth flux (two parts sulphur, one part potassium iodide, and one part acid potassium sulphate) is mixed with certain powdered minerals, placed on charcoal, or a plaster tablet, .and heated gently. The larger series o f tests are obtained on plaster, the sublimates differing in position and to some extent in color from those obtained on charcoal. Plaster tablets' are prepared by spreading a thick paste of plaster o f Paris and water upon a sheet of oiled glass, and smooth ing to a uniform thickness t 1 Is in to in). While still soft, the paste is cut with a knife into uniform slabs, 4 in b y U /2 in. i t is then dried, after which the tablets are easily detached from the glass. V. Flame coloration. A number o f minerals when heated color the flame, some at á gentle heat, some only at the highest heat attainable. Repeated dipping o f the mineral in hydrochloric acid usually assists b y forming volatile chlorides. A good method to cover all cases is as follows: Arrange a black background, such as a piece of charcoal, powder the substance finely, flatten the end o f a clean platinum wire and dip it in dilute acid, then in the powder, and hold it first just touching the flame near the blowpipe and then at the tip o f the blue'flame; again dip in the acid and.again heat as before. Concentrated sulphuric acid, and also a paste made of water, 4 1 / parte acid potassium sulphate »nr! 1 part of calcium fluoride, are also used to release certain flame-ccricring constituents, especially boron, phosphorus and lithium. Red flames of calcium, strontium, lithium, and the violet flames o f potassium in the presence of sodium, are m ost conveniently studied b y Merwin’a Color Scale (Science,
No. 1 Absorbed Blue-violet Strontium or lithium......................................
Greenish yellow Absorbed
No. 2
No. 3
Absorbed ( Violet and ( Violet-red Absorbed Absorbed
Absorbed f Violet and ( Violet-red Faint crimson Crimson
These elements are still more exactly distinguished b y use of a small pocket spectro scope. The mineral is moistened with hydrochloric acid and brought on a platinum wire into the non-luminous flame o f the Bunsen burner. This is viewed through the spec troscope and bright lines are seen. T he yellow sodium line is almost invariably present and the position of the other lines is best fixed b y their situation relative to this bright yellow line. VI. Bead tests with borax and with salt of phosphorus. The oxides o f certain elemente dissolve in borax and salt o f phosphorus and impart characteristic colors to the mass, which may differ when hot and cold and according to the degree of oxidation or reduction. Preliminary to bead tests, sulphides, arsenides, arsenates, etc, may be converted into oxides b y treating in a shallow cavity on charcoal at a duE red heat; first with a feeble oxidizing flame, then a feeble reducing flame, then again an oxidizing flame, and so on as long as odors or fumes are noticeable. T o mal?»» a bead. M ake a loop in platinum wire b y bending it around a pencil point so that the end meets but does n ot cross the straight part. Heat the loop, dip it into the flux, and fuse to a clear bead the portion that adheres. A dd more flux until the bead is of fuE rounded shape. W ith salt of phosphorus the ie a d should be held a little above the flame so that the ascending hot gases wiE help to retain the flux upon the wire. Touch the warm bead to the substance, place it in the O.F., and treat until clear. Note the colors, hot and cold. Then treat in the R .F . and note colors as before. Flaming. Some substances heated with a strong flame wiE give clear glasses until saturated; but if heated slowly and gently or intermittently, wiE yield opaque or enamel-like beads before saturation. VII. Testing with cobalt solution. Certain substances become colored, when moist* ened with a solution of cobalt nitrate in ten parts of water and then heated to a white heat. The test is usually made on charcoal. Certain other substances yield colors if strongly heated, cooled, and then moistened with the cobalt solution without reheating. Certain minerala boiled with cobalt solution are colored thereby.
5. X-RAY METHODS OF STUDY Recent years have witnessed the development o f X -ra y methods of mineral study. X -ray powder photographs m ay be used to aid in identifying many minerals. Clays, bauxite, fíne> micaceous silicates, poorly crystaUized metallics and other natural products, n ot readily identified in other ways, are often readily identified b y comparison of X-ray, diffraction photographs with known standards. The methods o f X -ra y study applicable to minpirals have been described b y Hull, D avey, W yckoff, Bragg, and others. Sirigte crystals are most frequently used for X -ra y studies, to yield information regard ing internal structures. The earliest to be developed was the method o f Laue, making use o f a pinhole beam of X -rays passing through a small crystal. The Braggs later devel oped the X -ray spectrometer, which depends upon the reflection o f X -rays from single crystal faces. ’ Lately, students of crystal structure have found the Weissenberg X-ray goniometer especiaEy useful.
6. POLISHED SURFACES OF METALLIC OSES Many textures and mineral combinations, not readily visible to the unaided eye, may be observed with the reflecting microscope. Polished surfaces must be prepared in advance with considerable care to produce flat, nearly uniform surfaces, as free from scratches as possible. Such surfaces m ay be etched and observed under the microscope and also examined b y reflected polarized light. Microchemical technique is also applied to small fragmente of- metallic minerals, removed from a polished surface with a needle while the surface is under microscopic
1-10
MLNEKALOGY
CONTACT MINERALS
observation. Among the comprehensive treatments of microscopic examination of metallic ores are the works of Van der Veen, Schneiderhôhn and Ramdohr, and Short.
7. EXAMINATION OF FRAGMENTS OF NON-OPAQUE MINERALS
1--11
Fragments of non-opaque minerals, about 100 to 120 mesh in size, m ay often be studied and identified b y the polarizing microscope. The fragments are placed on a glass slide immersed in an inert liquid of known refractive index, the indices of the minéral being compared with the index of the immersion liquid. Repeated mounts, made with liquids of different indices, b y comparison yield the indices of refraction of a mineral with a fair degree of precision. Other optical properties may be determined at the same time. The methods m ay often be applied to examination of non-opaque constituents of t.pilinga. The optical properties of many minerals observable with the microscope have been listed b y Larsen.and Berman.
Minerals of tin veins. Albite, amblygonite, apatite, arsenopyrite, bismuth, calcite, cassiterite, chlorite, columbite, fluorite, galena, kaolin, lepidolite, molybdenite, pyrite, pyroxene, quartz, scheelite, wernerite, wolframite. Minerals of apatite veins. Albite, amphibole, apatite, biotite, calcite, enstatite, hematite, ilmenite, magnetite, oligoclase, pyrite, quartz, rutile, sphene, tourmaline, wernerite. Minerals due to volcanic exhalations. Alunite, sassolite, sulphur, and relatively a™aii quanti ties of other species, as amphibole, hematite, sal-ammoniac, etc, occur as the result of gases given off during volcanic action.
8. EXAMINATION OF THIN SECTIONS
These exist as sédiments precipitated from solution in natural waters, springs, rivers, marshes, lakes, seaa, and oceans. From springs. Alunogen, aragonite, barite, baimte (?), calcite, celestite, chalcedony, cinnabar, fluorite, hydrozincite, kalinite, limonite, pyrite, sassolite, aiderite, sulphur. From soda and borax lakes and lagoons. Anhydrite, calcite, borax, celestite, cerargyrite, colemanite, dolomite, embolite, gold, gypsum, halite, mirabilite, sassolite, soda nitre, sulphur, trotta, ulexite. From oceans, seas, lakes, and marshes. Apatite, anhydrite, bauxite, boracite, calcite, carnallite, celeatite, cerargyrite, dolomite, epsomite, gypsum, halite, kainite, Meserite, limonite, siderite, wad. Local saline residues (often incrustations or efflorescences). Alunite, alunogen, chalcanthite, copiapite, epsomite, kalinite, mirabilite.
The structures and textures o f non-opaque minerals are-best examined in thin sections beneath the microscope. T he polarizing microscope of the types manufactured by E. Leitz, Zeiss-Winkel, Bausch and Lomb, or the Spencer Lens Co, are useful for this purpose. M any optical criteria n ot obvious in ordinary specimens m ay be used in such an examination- The methods have been outlined b y Winchell, Johannsen, and Rogers and Kerr.
10. MINERALS FOUND IN SALINE RESIDUES
OCCURRENCE AND ASSOCIATION OF MINERALS 11. MINERALS IN GRAVELS, SANDS, CLAYS, AND MARLS 9. MINERALS OF ROCKS AND VEINS Associates. M ost minerals are found under a variety o f conditions, and with different groups of associates. T he most probable associates of any mineral in any particular occurrence are: 1. The com mon minerals of that deposit. 2. Minerals containing some prominent element or elements of the given mineral. In the following lists, which include the rock-forming minerals, com mon minerals, and those of_economic importance, the species in italics are relatively rare. ‘ Minerals of the igneous rocks. These minerals in general have either separated from a fusion solution or “ magma ” (each separating whenever for the existing temperature and pressure the magma, is supersaturated with it), or they have formed later, as secondary minoralq. b y the decomposition or alteration of the primary minerals. Principal primary minerals of igneous rocks. Amphibole (hornblende), biotite, chrysolite (olivine), enstatite,’ hypersthene, leueite, muscovite, nepheline (elaeolite), orthodase, plagioclase, pyroxene, (augite), quartz, sodalite. _ Minor primary minerals .of igneous rocks. A nalcite, apatite, chcdcopyriie, chrysoberyl, chromite, cinnabar, corundum, epidote, garnet (almandite, andradite, pyrope), goethite, gold, graphite, hematite, ilxnenite, lepidolite, magnetite, m ülente, molybdenite, monazite, pyrite, pyroxene (diopside), pyrrhotite, rutile. Secondary minerals haTigneous rocks. Albite, alunite, analcite, apophylliie, aragonite, azurite, barite, cafcite, cfaabazite, chalcedony, ckalcanthite, ckalcopyrite, chlorite, ehrysocolla, copper, datolite, epidote, kaolin, lepidolite, limonite, magnetite, malachite, muscovite, natrokte, opal, pyrargynte, quartz, serpentine, aiderite, sphalerite, stibaite, tale, tetrahedrite, turquois,_weruente. _ . . , Minerals of pegmatite veins. Vein-like portions of gramtea or other igneous rocks in which the minerals of the rock are found in much larger crystals and in which many other minerals occur not noticed in the adjoining rocks. . „ , , .. ,, .. , . _ , ... Albite amblygonite, apatite, beryl, biotite, camtente, chabaztte, cklorUe, chrysoberyl, columbxte, crvoîite diamond, galena, garnet (almandite and spessartite), graphite, lepidolite, magnetite, microcline, molybdenite, monazite, muscovite, nepheline, orthodase, pyrxte, pyrrhotite, quartz, spodumene, topaz, tourmaline, uranimte, zircon. Minerals o f ore veins. For convenience these have been listed under two headings: Minerals in zone o f weathering or oxidation, and minerals of unoxidized zone. In zone of oxidation.. Anglesite, azurite, brochantite, calamine, celestite,; cerargynte, cerussite, chalcantkite, chrysocolla, copper, crocoite, cuprite, embolite, erythrite, goethite, gold, iodyrite, limonite, malachite, manganite, mimetite, pyromorphite, rhodoehrosite, sidente, silver, smithsonite, strontianite, sulphur, vanadinite, vivianite, wulfenite. In unoxidized
Minerals common to all. Biotite, calcite, chlorite, garnet, hematite, kaolinite, limonite, mag~ rietite, muscovite, orthodase, plagioclase, pyrite, pyrophyllite, pyroxene, rutile, siderite, sphene, tourmaline. Gem minerals and ores in gravels and sands. Cassiterite,. chrysoberyl, chrysolite, corundum, diamond, gold, ilmenite, monazite, platinum, spinel, tourmaline, topaz, zircon. Minor minerals in gravels and sands. Amphibole, andalusite, apatite, cyanite, dolomite, ensta tite, epidote, hypersthene, microcline, sepiolite, serpentine, sillimanite. Ores in clays. Galena, limonite, manganite, psilomelane, pyroluaite, wad. Minor minerals in clays and marls. Amphibole, aragonite, barite, celestite, gypsum, halloysite, orpiment, realgar,.strontianite, vivianite. Minerals in sandstones. Chiefly quartz, orthodase, plagioclase, limonite, muscovite. Minor minerals are carnotite, galena, gold, marcasite, manganite, pyrite, pyrolusite, aiderite, sphalerite. Minerals in sedimentary limestone. Aragonite, calcite, dolomite, fluorite, galena, limonite (bog ore), nitre, opal, aiderite, soda nitre, sulphur, sphalerite. In serpentine and soapstones. Amphibole, aragonite, arsenopyrite, calcite, chlorite, chromite, chrysolite, cinnabar, diamond, dolomite, enstatite, epidote, garnet (pyrope), gamierite, ilmenite, magnesite, magnetite, phlogopite, platinum, pyroxene, pyrophyllite, quartz, sepiolite, serpentine* talc.
12. CONTACT MINERALS When an igneous rook penetrates a preëxisting rock the heat, pressure, and evolved vapors frequently produce new minerals at and near the surface o f contact. Contacts with limestone. Amphibole (tremolite), anorthite, biotite, bornite, chondrodite, dinozofcite, corundum, danburite, enstatite, epidote, fluorite, garnet (grossular and andradite), graphite, lazurite, molybdenite, phlogopite, pyrite, pyroxene (diopside), scheelite, spinel, tourmaline, vesuvianite, wemerite, wollastonite and zoisite. Contacte with silicate rocks (clay, shale, slate, or crystalline schists). Amphibole (hornblende), andalusite (çhiastolite), biotite, chlorite, corundum, kyanite, epidote, garnet, ilmenite, magnetite, pyroxene (augite), quartz, rutile, sillimanite, spinel, staurolite, sphene, tourmaline, topaz, wemerite, zircon.
Minerals of Metamorphic Rocks 'Hie minerals o f the metamorphic rocks include many species o f the original rocks, and many species already listed under contact minerals. A partial list follows: In Crystalline limestones, and dolomites: amphibole (tremolite), apatite,, aragonite, calcite,
1-12
M IN E R A L O G Y
tite, rhodonite, serpentine, smithsonite, spinel, talc, willemite, zincite, zircon. In Gneisses and Schists: the contact minerals of the second list (contacts with silicate rocks). Also aetinolite, apatite, beryl, biotite, calcite, chalcopyrite, chrysoberyl, datolite, fluorite, gibbsite, graphite, hematite, molybdenite, monazite, muscovite, orthoelase, plagioclaae, pyrite, pyrophyllite, pyrrhotite, tale, tetrahedrite, vesuviamte, zeolites.
th e
u ses
of
m in e r a l s
This list includes only the principal uses o f the minerals as such, and their uses aa the material from which other substances are directly extracted or manufactured. The secondary products derived from these primary products are not mentioned.
13. USES OF MINERALS IK THEIR NATURAL STATE Abrasives. Quartz, garnet, opal (tripolite and diatomaceous earth), corundum and emery, riteTT.nr.il (bort), orthoelase. Leucite and alunite rocks have been used as millstones. Building stones. Quartz, orthoelase, plagioclase, muscovite, biotite, pyroxene and amphibole In varying proportions, forming igneous rocks commercially known as granite and trap; talc and pyrophyllite (soapstones), serpentines; calcite and dolomite (limestones and marbles), quartz ( B a n d s tone). , . . . . Electrical insulators. Muscovite, phlogopite, calcite (marble), andalusite, kyamte, sillimamte, and dumortierite. . , , Fertilizers. Camallite and kainite for potash; soda nitre for nitrogen; gypsum and calcite for lime; apatite (phosphate rock) for phosphoric acid. Muscovite and biotite as retainers of mois ture. Fluxes. Calcite, fluorite, borax, pyrolusite. Glass. Chiefly quartz (sand and sandstone) and calcite (limestone) ; to a less extent orthoelase, plagioclase, cryolite, and pyrolusite. Lubricants. Graphite, talc, muscovite. _ . Paints and pigments. Hematite and limonite as "metallic paint” ; the same minerals associated ■with clay, “ ocher.” Calcite (chalk) as “ whiting” ; wad, barite, gypsum, asbestos, muscovite, talc, kaolin, quartz, magnesite, azurite, graphite, asphaltum, rutile. Paper manufacture. Tale (fibrous), gypsum (selenite), as constituents of sheets. Bante, cal cite, kaolin, magnesite, bauxite, muscovite, for weight and glaae. Porcelain, pottery, etc. Kaolin and other clays, quartz, orthoelase, albite, halite, gypsum and pyrophyllite. , , , Precious stones. Diamond, beryl, emerald, corundum (sapphire and .ruby), chrysoberyl (alexandrite), garnet (demantoid), spinel (ruby spinel)i Semi-precious stones. Other varieties of beryl, corundum, chrysoberyl, spinel, and garnet. Also opal, chrysolite (peridot), quartz (ame thyst and yellow), topaz, tourmaline, turquoise, zircon, spodumene (künzite, hiddenite), orthoelase (moonstone). Ornamental stones. Amber, chalcedony (onyx, earnelian, sard, agate, etc), quartz (rose cat’s eye, aventurine, smoky, etc), orthoelase (amazon stone), plagioclase (labradonte and sunstone)i Amphibole (jade), lasurite (lapis lazuli), malachite, azunte, calamine, smithsonite, chrysocolia, fluorite, gypsum (satin spar), Serpentine, hématite, pyrite, rhodonite, talc. Occasional faceted stones are cut from apatite, andalusite, cassiterite, chondrodlte* cyamte, pyroxene (diopside), enstatite, epidoté, prehnite, staurolite, sphene and vesuviamte. Refractory and Seat insulators. Asbestos, bauxite, chromite, dolomite, graphite, ilmenite, kaolin, magnesite, muscovite, opal (diatomaceous earth), serpentine (chrysotile), quartz, pyrophyllite, talc (soapstone), sillimanite, andalusite, kyamte and vermiculite. Rubber manufacture. Sulphur, stibnitè, barite, calcite, talc, pyrophyllite. Soap and washing powders, toilet articles. Borax, opal (diatomaceous earth), talc, quartz, magnesite, orthoelase. , Sundries. Coloring or decolorizing: pyrolusite, psilomelane, rutile. Condiments: haute. Explosives: nitre, sulphur. Filters: opal (tripolite). Enamels: fluorite, borax. Matches: stibnite sulphur. Optical: quartz, calcite, fluorite, gypsum, muscoviWi Pencils: graphite, talc, pyro phyllite. Pipes: sepiolite (meerschaum), succinite (amber).
14. PRODUCTS EXTRACTED OR MANUFACTURED DIRECTLY FROM MINERALS Aluminum from’ bauxite, possibly gibbsite, with cryolite as flux. Alundum (AljOj) from bauxite. Aluminium sulphate and alum from alunite, cryolite* bauxite, kaolin. Antimony from stibnite and its alteration products and lead ores carrying antimony. Arsenic from araenopyiite and sometimes from smaltite, cobaltite, enargite, etc. Barium hydroxide otid barium sulphide from barite. Beryllium and beryllium oxide from beryl. Bismuth from native bismuth, bismutite, ahd bismite. Borax and boric acid, from coiemanite, ulexifce, borax, and sassolite.
PROD U CTS
EXTRACTED
D IR E C T L Y
FROM
M IN E R A L S
1 -1 3
Bromine from halite (salt brine). Cadmium from sphalerite and smithsonite containing greenockite. Calcium oxide (lime) from calcite (limestone). Calcium sulphate (hemi-hydrate) or plaster from gypsum. Calcium superphosphate from apatite. Cements from calcite and clays. Carbonic acid from magnesite and calcite. Chlorine from hydrochloric acid and pyrolusite, the former being derived from halite. Chromium alloys, especially ferrochrome from chromite. Cobalt oxide and cobalt arsenate (zaffre) from smaltite, cobaltite, and cobaltiferous limonite. Copper principally from chalcocite, native copper, chalcopyrite, bornite, cuprite, malachite, and azurite, although enargite, tetrahedrite, atacamite, brochantite, chalcanthite, and chrysocolia are all sources of copper in certain districts. In addition to these the iron sulphides often carry copper which is extracted after burning for sulphuric add. Copper sulphate from chalcopyrite. Gold from gold and the gold tellurides (sylvanite, oaiaverite, petzite), from silver and copper ores and from pyrite, arsenopyrite and pyrrhotite, and sphalerite and other sulphides or tellurides. Hydrochloric add from halite. Hydrofluoric acid from fluorite and cryolite. Iodine from sodium iodate obtained from soda nitre. Iridium from iridosmine. Iron from hematite, limonite, magnetite, and siderite, goethite, and turgite (commercially in cluded with limonite), some ilmenite, and rarely residues from the roasting of pyrites. Iron sulphate (ferrous) or “ copperas" from pyrite and chalcopyrite. Iron manganese'alloy from franklinite and certain manganiferous hematites and siderites; also from pyrolusite, psilomelane, manganite and other manganese oxides. Lead, chiefly from galena aad cerussite. Angleaite and pyromorphite sometimes occur in quantity. Lead sulphate (sublimed white lead and blue lead) from galena. Lithium carbonate from spodumene, lepidolite, and amblygohite. Magnesium from carnallite. _ _ i_ . Magnesium carbonate from dolomite. Basic carbonate from kieserite. Magnesium oxide from magnesite, and indirectly kieserite. Magnesium chloride from carnallite. _ Magnesium sulphate (epsom salts) from kieserite and less often from magnesite and dolomite. Manganese alloys from pyrolusite, psilomelane and braunite, or with intermixed rhodochrosite and rhodonite. Manganese salts from pyrolusite. Mercury from cinnabar. Molybdenum and ammonic molybdate from molybdenite. . _ Nickel from pentlandite, garnierite, nickeliferous pyrrhotite, and to a less extent from millente, niccolite and the cobalt minerals, cobaltite and luuueite. Nitric acid from soda-nitre and nitre. Palladium from copper ores and platinum. Phosphorus from an impure calcium phosphate (sombrerite), or from bone ash. Platinum from native platinum and sperrylite, and from some gold and copper ores. Potassium from carnallite. Potassium dichromate from chromite. Potassium sulphate from kainite. Potassium nitrate from soda nitre and carnallite. Radium chloride from uraninite, camotite, and autunite. Rhodium from platinum. Selenium from sulphur, chalcopyrite, and pyrite. Silicon carbide (carborundum) from quartz and coke. Silicon alloys (ferro-silicon) from quartz. Silver from native silver, argentite, cerargyrite, embolite, proustite, pyrargyrite, and less im portant, hessite, polybasite, and iodyrite. Included in other minerals, notably, galena and cerussite, but also in copper ores, manganese ores and with gold in pyntc and arsenopyrite. Sodium borate (borax) from coiemanite, ulexite, sassolite, kemite, and native borax. Sodium stannate from cassiterite. _ Sodium sulphate (salt-cake) from halite, and from this, caustic soda, carbonate, bicarbonate. Strontium nitrate and ckloride from strontianite. . Sulphuric acid, sulphurous acid, from native sulphur, pyrite, marcasite, chalcopyrite, sphalerite, pyrrhotite, and other sulphide ores. Tantalum from columbite. Thorium nitrate and thorium oxide from monazite, thorite, thonamte. Tin and sodium stannate from cassiterite. Titanium, titanium oxide, and ferro-titanium from ilmenite. Titanium carbide from rutile. Tungsten, ferro-tungsten, from wolframite and scheelite. Tungstate of soda from wolframite. TJranium yellow or sodium diuranate from uraninite, camotite. Vanadium, and ferro-vanadium from camotite, patronite, roscoelite, vanadinite, desclomls. Vanadic oxide from mottramite.
1 -1 4
MINERALOGY
Zinc, “ nine dust," and zinc oxide from sphalerite, smithaoaite, and calamine; and in New Jersey, wiilemite and ziacite. Zinc sulphate from sphalerite. Zirconium oxide from zircon.
DESCRIPTIVE AND DETERMINATIVE TABLES Rare species without economic value are omitted. Their inclusion would greatly increase the complexity of the tables and also increase the difficulty o f determination. Rare minerals require special methods beyond the scope o f a simple set o f mineral tables; chemical analyses, optical, and X -ra y determinations are usually necessary. Due to the limited space the species are described only in the tables, and the accompanying diagrammatic index will enable the user to find-a brief-description o f any species. (For example, scheelite. A reference to 22 in the diagram will give composi tion, crystal system, hardness, specific gravity, colors, solubility, flame coloration, behavior with fluxes a id general appearance.) . The uses and occurrence of minerals are summarized m separate tables. In using tfae tables the customary precautions are understood to be taken: 1. Tests must be made upon homogeneous materials, and lusters and colora observed on fresh fractures. . 2. Classifying tests must be decided; n ot weak, nor indefinite. I f undecided, tne species on both sides o f the dividing line must be considered. . 3. tests should be assumed to be within say one half; th at is, a determination H - S should for safety be taken as 4.5 to 5.5. A s shown b y the accompanying key, the principal subdivision is between metallic and non-metaliic luster. T he blowpipe test is made subordinate for minerals o f metallic luster and minerals o f non-metallic luster with colored streaks; but, for minerals o f nonmetalUc luster w ith white streaks, experience proves that the blowpipe or the microscope iead to a determination with less repetition than such qualities as color and hardness. A novel feature o f the tables is the “ scheme within a scheme,” b y which the order of testing m ay be varied. For instance, in 16, 1 7 ,1 8 the arrangement is b y blowpipe tests in order o f hardness, but the parallel columns permit color to be used as the classifying test; that is, the order of testing m ay be color and hardness or blowpipe test and hardness. Similarly in 5, 6 the arrangement o f the metallic white and gray minerals is b y streak and hardness, but the parallel columns permit the behavior on charcoal in oxidizing and reducing flame to be used as the classifying test; that is, the order o f testing m ay be color, streak and hardness, or color Mid behavior on charcoal. Chemical symbols are used only for the formulas o f the species and for the common solvents, H a , H 2SO 4, HNOs, K O H , etc. Aside from these a few abbreviations are used, the principal being: . .. Systems of crystallization are indicated b y the lettera: I (Isom etnc), T (Tetragonal), O (Orthorhombie), M (Monoclinic), T ri (Triclinio), H (Hexagonal). _ Terms in blowpipe teste. Soda for sodic carbonate, S. Ph. for salt of phosphorus, O. F. and R . F. for oxidizing and reducing flame, Co. Sol. for cobalt solution, coal for The + sign in any column opposite any mineral indicates that the quality indicated is a character of that mineral. , , „ , . ., , ' The following diagram furnishes at a glance the procedure t o be followed in identifying an unknown mineral :
DESCRIPTIVE AND DETERMINATIVE TABLES
1 -1 5
Minerals o f Metallic or Sub-Metallic Luster, Black or Nearly Black in Color (Including arbitrarily some dark-colored minerals of doubtful luster) *
On coal in 0 . F. and R. F.
Crystal system: name, composition, hordneas and specific gravity
Residue
Odor Sublimates As
S02
io I o 13 ¡3 a
Mag netic
* 1
Fusibility
Solubility
Heated in closed tube
3 f? Mn02 H ta H = i to 2.5 M
In CuSOi solution Shining flakes and in contact with masses or dull, impure zinc quickly cop masses. Soft, greasy per-plated. (Mo^ t^nd cold,to the touch. lybdenite is slowly Shining mark on paper. plated)
SbjSj H =2
Slowly burned
0=2.1 to 2.2
+ G »4.7 to 4.8 +
Dense white
Becomes brown 1
+
G «4.5 to 4.6
I 8
AgjS H « 2 to 2.5
+
1.5
+
1
+
+
2
+
+
+ G =7.2 to 7.6
i W
»4
+
AgsSbS* H =2 to 2.5 G =6.2 to 6.3
PbS H<=2.5
+
Yellow R. F.
0. Polybasite....................... (Ag-CubSbSa H = 2 to 3 G = 6 to 6.2
+
Donee wbito. Some yellow
+
Dense white
+
+
+
Volatile white
Tenori te............................... CuO H »3 G » 5.6 to 6.2 I. Tetrahedrite.................... CusSb2S7 H = 3 to 4.5 G =4.5 to 5.1
Sol. HNO¡¡. Fuses. No sublimate (Residue S. Ppt. with HC1) Sol. HNOj (white residue)
Fuses. Slight D ecom posed by Fine-grained, often dis-. red subli KOH. HC1 gives seminated. Sometimes crystals. Soft but brit orange ppt. mate tle.
hot HC1
Decrepitates. "Bismuth Flux” on Granular and cleavable coal gives greeniak masses and cubic crys A little white subli yellow sublimat« tals which cleave into oubes. mate
Sol. HN0a. F u ses. N o M etallic residue Beat known in six-sided (Ppt. with sublimate ignited with HC1 plates. In thin splint HC1) gives azure blue ers is cherry red by flame transmitted light.
+
2 to 2.5
Sol. HN0 3 F u ses. N o E m era ld green Compact masses, nod (residue S) sublimate flame made azure ules and disseminated. blue by HC1 Often coated with the g reen c a r b o n a te . Rarely crystals.
+
times
+
Dense white
1.5
+
Sol. HNOj
(evolution Cl)
water
Like enargite
Dull earthy masses, powder and shining Fine-grained masses and “ tetrahedral ” crys tals. Sometimes coated with ohalcopyrite.
Massive with smooth thystino 0. F. So rounded surfaces, or lutions usually s ta la o titic . N ever give white ppt. crystallized. with H2SO4
+
Infus. 0. F. Sol. (boiled Fus. diff. with tin is R. F. violet)
S. Ph. bead. O.F. red. R. F. violet grains, sand and tabu lar hexagonal crystals.
+
Infus.
Solutions give yel low ppt, with am m on ia . B o ra x 0. F. “ flames” y ellow enamel near saturation
-G »4.5 tp 5 times
Like enargite
Fuses. Dark red s u b li mate
G =4.5 to 5
I. Uraninite........... .............. UOrUO*, PbO, etc. H =5.5 G = 9 to 9.7
M etallic residue Columnar, granular and Yellow subi, ignited with HC1 compact masses and then fuses gives azure blue prisms, sometimes ra and gives flame diating. red subì.
Infus. 0. F. Soluble Fus. R. F.
+
Sol HNOs (yellow)
&
o a
Needle crystals, or bus* gives greenish yel like or felted; also com low sublimate pact and fibrous mas sive.
1
Sol. HN0s
Pi
With eoda, metallic Coatings and dissemi Ag and S reaction nated plates. Rarely crystals. Cuts like metallic lead. Streak is shining.
+
MnOî, BaO, HjjO, etc.
FeTiOü H = 5 to6
Fuses. Subli Made yellow by Bright columnar, bladed mate black KOH and par or fine-grained masses, odor HiS) hot, red cold tially dissolved. less frequently in pris HC1 gives orange matic crystals or inter laced bunches of needle ppt. crystals.
Sol. (witb Brownish red odor H2S; sublimate
G =5.5 to 5.8
0 . Enargite......................... CujAsS4 H =3 G =4.4
H = 5 to 6
Yields oxygen Colors borax ame Bright, easily bruised Sol. HC1 thystine in 0. F. needles or fibers or (evolution and often dull masses. Dull mark water of a> on paper.
G =7.4 to 7.6
PbîSbzSi H «2.5 G = 5.i to 6
C uíS H = 2.5 to 3
reddens
Appearanoe
11
Insoluble C H = lt o 2
Other tests
Massive botryoidal or granular. Pitch-like luster. Rarely small crystals.
Ü CO
8 t-t H3
% g y
Sd
g
fe 3 H 1-9
wI H-*
<1
Minerals of Metallic or Sub-Metallic Luster, Black or Nearly Black in Color— Continued_____________________________ Jj* On coal in O. F. and R- F. Crystal system:
Residue
Odor Sublimates
hardness and specific gravity As
BO*
I
1o •a S
Fusibility on coal
I*
Heated in closed tube
Solubility
5.5 inR . F.
+
Sol. HC1
heating but loses masses and sand and m agnetism in octrahedral crystals. Strongly attracted by 0 . F. a steel magnet. Some times, itself a magnet (lodestone).
M mq
g jj
+
Infusible
+
Infusible
Fused KHSO4 and Prismatic crystals, often boiled HC1 and iridescent, in pegma tin give deep blue tite dikes. Also mas sive.
Insoluble
Fc(CbTa)iOs H =6 G “ 5.4 to 6.5
COtf MttzOg H = 6 to 6.5
G =4.7 to 4.8 +
Dense white
I
+
AgsSbSg 11=2.5 G =5.7 to 5.8
3 A K
ZnS H »3 .5 to 4
White cold
+
G =>3.9 to 4.1
1
Appearance
z «
FejOi a »5.5 to 6.5 G =4.9 to 5.2
3*
Other tests
+ MnO (OH) H »4 G=»3.7to4!
M
Fine-grained masses and A little water Colors bora* ameSol. HC1 occasional small pyra (evolution no oxygen S olution often mids almost isometric. Cl) yields silica jelly Veins or crusts with a Sol. HNO* Subl. black D ecom posed by White resi hot, red cold KOH. HCl pro luster showing red tint, duces orange ppt due in thin layers. Rare crystals. Streak purplish-red.
Black and gray crystals Infusible Effervesces. No sublimatt Sublimate on cos made bright greei Gives odo (or fus. grained masses. Streak by ignition wit! with diffi HsS pale brown. cobalt solution culty) CrystalB often grouped Borax O. F. ameMuch water. Infusible. Sol. HC1. (Become« (Evolves eive, granular or stagen Cl) brown) iactitie. Streak dark brown.
----Limonile........... ............... F^(OH)8*FegOj H =5 to 5.5 G = 3 .6 to 4
+
5 to 5.5 to Soluble
Often reacts ror Cellular and pulveru Reddens. Yields much manganese and len t or as com pact water may give jelly masses often radiated or stalactitic and with residue varnish-like surfaces. Never crystallized. Streak yellow ish brown. Often reacts for Occurs massive but is Reddens. Yields water manganese. (Soda beet known as crys bead O. F. bluish tals, often flattened like scales, or neediegreen) like, or in parallel posi tion. These shade into feather-like and vel vety crusts.
Ü a G0
O. Goethito....................... FeO (OH) H«*5 to 5.5 G =4 to 4.4
5 to 5.5 to slag
Soluble
T. Hausmannite.................. MD8Û4 H » 5 to 5.5 G =4.7 to 4.8
Infusible
Sol. HC1. (Evolves Cl)
M. Wolframite.............. (FeMn) W0 4 H =5 to 5.5 G =7.1 to 7.5
Partial 3 to 4 (crystal line bead)
Solutions become Heavy monoclinic crys deep blue on addi tals and eleavable, tion of tin. Solu bladed and granular tionofS.Ph.bead masses. Streak brown ish black. in HC1 beBt
§
I
Boras O. F. ame Granular masses occa sionally in twinned thystine p y ra m id s. S treak chestnut brown.
Ilmenite............................. FoTiOa H »5 to6 G =4.5 to 5
+
InfuB. O. F. Partial Slightly R. F.
Filtered solution Usually compact mass boiled with tin be es, often thin plates or imbedded grains or as comes violet sand. Rarely in tabu lar hexagonal crystals. Streak brownish red.
I. TJraninite....................... U0 8-U0 2, eto H=5.5 G =9 to 9.7
Solution gives yel Botryoid&l or granular low ppt. with am with pitch-like luster. monia. Borax R Rarely in small isometStreak F. green, near sat ric crystals. dark green. uration blackens
I. Chromite.................... FeCr-jOi H=5.5 G =4.3 to 4.6
+
Infusible O. F. Slightly R.F.
Insoluble
Borax or S. Ph., Granular or compact O. F. or R. F., em or rarely in small oc tahedral crysta ls. erald green cold Pitch-like luBter. Often with serpentine. Streak dark brown.
Ü P3
xjl
h* t—‘ ÇO
Minerals
of Metallic or Sub-Metallic Luster, Black or Hearty Black in C d o r -C m * » *
k On coal in O. F. and R.. F. Residue
Odor
Crystal system: name, composition, hardness and specific gravity
■O o2
Sublimates
Solubility
Heated in closed tube
2 fl Infusible
+
H. Hematite.................. Fe20 8 H = 5.5 to 6.5 G = 4.9 to 5.3
+
Coarse to fine micaceous masses and tabularor coarser crystals with brilliant luster. Occa s io n a lly k id n e y shaped. Streak brown ish red.
Soluble
Infusible
Insoluble
Infusible
Slowly in HC1 evolv ing Cl
O. Columbite................. Fe (CbTa)20 9 H =6 G =5.4 to 6.5 Slight white
I. Franklinite........... . •-
(FeMnZn) O (FeM n)î08
H = 6 to 6.5
G ==5 to 5.2
Infusible
Insoluble
-4- Infusible
Insoluble
T. Rutile............................. H = 6 to 6.5
Appearance
Other tests
-1
S0 2
Ab
Fusibility on coal
G =4.1 to 4.2 Some varieties give white sublimate
T. Casaiterito...................... Sn02 H = 6 to 7 G=6.8to7.1
and brilliant, Fused with KOH and boiled with olten iridescent, pris matic crystals. Streak HCi and tin gives dark red. blue solution. Sodabead O. F. blu C o m p a c t m a s s e s , rounded grains and ish green octahedral crystals. Slightly magnetic. Red zincite and yellow to green wiUemite axe associates. Streak dark brown. S. Ph. bead in R. violet
Masses and crystals with considerable luster. Streak pale yellow.
With soda or sul Brilliant crystals, usu phur on coal is ally with brown tinpo. strong heat a subl Streak pale yellow. yellow hot, white cold, made bluish green by ignition with cobalt solu tion
of Metallic Luster, Tin-W hite, Silver-White, Lead-Gray or Steel-Gray in Color On coal in O. F. and R. F. Odor
Residue Fusi bility
Sublimates S02
+
White, O. F. Yellow R. F.
+
Sol. HCI hot. Decrepitates. Greenish yellow subl. Lead-gray granular and cleav(Crystals A little on coal with Bi flux able masses and cubic crystals on cooling) white subli which cleave into cubes. mate
Dense white
1.5
Sol. HIÍQ*
Non-volatile white subli mate (yel low hot)
1.5
Sol. HNO? (green with white residue)
I. Linnseite........................ (Co-Ni)sS4 H=5.S G =4.8 to 5
+
+
+
Fuses. Dark- M e t a llic re sid u e Steel-gray fine-grained masses red subli ignited with HCI and tetrahedral crystals. mate gives azure blue flame Subl. on coal becomes Steel-gray, massive, granular. bluish green by igni Often intermixed with yellow tion with cobalt so chalcopyrite. lution
Sol. HN0 3 Slight yellow Borax deep blue O. F. Steel-gray granular or com (red with sublimate and R. F. pact masses, or small octahe sulphur dral crystals. residue) Volatile white sublimate
Easy Sol. HNOa Unaltered (red with white resi due)
Like linnæite
Gray masses and tin-white crystals. Often a red tarnish.
1-21
I. Cobaltite....................... CoAS2 H=5.5 G « 6 to 6.1
Steel-gray to dark-gray needle crystals, or hair-like or felted; also compact and fibrous mas sive.
TABLES
I. Tetrahedrite.................... Some times CugSbíSj H = 3 to 4.5 G =4.5 to 5.1
Sol. (with Subl. brown Like galenite odor H2S) ish red cold
D E T E R M IN A T IV E
Dense white Some yel low, volatile
+
Appearance
Sol. HCI hot Fuses, yields Solution in upper part Lead-gray columnar or fine (odor H2S) subl. black test tube repptd. as grained _masses or prisms. hot, brown orange by H2S from Cleaves into lath-shaped frag ish red cold dissolving portion ments.
O. Jamesonite................... PbSb2S6 H =2.5 G =5.5 to 6
I. Stannite................. (Cu-Sn-Fe) S ' H =4 G =4.5
Other teBts
AND
I. Galenite........................... PbS H = 2.5 G «7.4 to 7.6
Heated in closed tube
I3 Dense white. Volatile
O.Stibnite.................. SbzSa H =2 G =4.5
Solubility
D E SC R IP TIV E
Crystal system: name, composition, hardness and specific gravity
1-22
Minerals of Metallic Luster, Tin-White, Silver-White, Lead-Gray or Steel-Gray in Colot—Continued On coal in 0 . F. and R. F. Crystal system: name, composition, hardness and sp nfio gravity
NOT BLACK STREAK
I. Sperrylite. PtAs2 0 = 10.6 H = 6 to 7
+
+
+
Volatile white sublimate
+
Slight vol. sublimate
Easy Sol. HN0 8 Mirror and Like linnsite black subli (red to mate green)
Subl. of small With Bi flu* on plas A tin-white liquid found in scat ter, volatile, scarlet tered globules or in cavitieB metallic with cinnabar. and yellow subl. globules
Volatil Sol. HNOj izes Infua.
Slight white and bronze
Steel-gray masses and tin-white crystals usually cubes, often with erythrite.
In open tube white Tin-white grains and minute subl. and spongy crystals residue
G = 13.6 +
Appearanoe
Sol. HNO« Brownish red After short ignition Tin-white to gray masses or subì. Later on coal, dissolves in crystals often striated, the (sulphur residue) mirror : and HCI with odor of sections of which are rhombic H2S and yellow ppt. and rectangular. black Easy Insoluble
+
+
H. Molybdenite................... MoS H = 1 to 1.5 Gi =4.6 to 4.9
Other tests
r Volatile white sublimate
G =6.4 to 6.6 +
Heated in closed tube
Solubility
Sol. cono. HNO# (luminous)
Colors flame yellow Bluish gray scales and foliated ish green and is red maBBee cleaving to flexible non-elastic plates. Streak dened greenish-gray on glazed porce lain.
Grayish white
+
Sol. HNO* (gold resi due). In hot H2S0< purple.
The Bublimate placed Steel gray to silver white, some on porcelain moiB times inclined to yellow. Intened with conc crusting or in small veins. H2SO4 and warmed Streak silver white to gray. is violet
H. Bismuth......................... Some* times Bi (often with As) H =2 to 2.5 G =9.7 to 9.8
Yellow and -f white subli mates
+
Sol. HNO* (white ppt. by water)
Chocolate brown and Silver white with reddish tinge, red subl. with Bi often " branching " or in iso flux on plaster tablet lated grains. Streak silver white.
Slight gray sublimate
+
j
|
Gold tellurides................... (Au-Ag)Tea H « 1.5 to 2.5 G=7.9 to 9
(Au-Ag)Te H =2 to 2.5 G =8.3 to 8.6
Slight gray sublimate
+
Pt (Fe) H =4 to4.5
Tin-white, fine-grained or mi nute hexagonal prisms. Streak tin-white.
Sol. HNO* or H2S04
times
volatile
+
1
Volatile white +
Some times
-f
Whitevolatile
Sol. HNOb (green with white reddue) +
G = 14to 19
+
+
Infua.
Pale '* silver ” white branching and g iv e cu rd y crystals, wire flakes and white ppt. with HCI masses. Tarnishes brown to black. Malleable. Streak sil ver-white.
Soluble
Volatil Sol. HNOj izes
G =5.6 to 5.7
H. Iridoamine...................... (ir-Os) H = 6 to 7 G = !9 to 21
Like gold telluride
+
+
CugSbaS? H =3 to 4.5 G =»4.5 to 5.1
Easy In hot H2S04 is purple
Burns with yellowgreen flame ated. Very brittle.
Decrepitates Solutions blue with brownish ammonia. Roasted and tetrahedral crystals. red subli residue ignited with Streak cherry red. mate HCI azure blue flame scales and nuggets. Malleable and sometimes attracted by the magnet. Streak shining steel-gray.
TABLES
Ag H =3.5
Gray, fine-grained to coarse grained or in isometrio crys tals. Streak gray.
D E T E R M IN A T IV E
STREAK
Antimony............................ Sb H =3 to 3.5 G =6.5 to 6.7
Like gold telluride
Mirror flame
Sol. aqua regia only
unpleasant odor
black. Usually massive, with rounded surfaces. Sometimes in concentric layers. Streak tin white.
flat grains and hexagonal plates. Streak steel gray.
1-23
Infus. Insoluble (Un pleasant odor)
AND
WOT BLACK
I. Silver............................... Ag H = 2 .5 to 3 G = 10.1 to II.1
Easy Sol. HNO*. In hot H2S04 purple
D E SC RIPTIV E
H. Tellurium....................... Te with-Se-S H = 2 to 2.5 G=6.1 to 6.3
WITH
M IN E R A LO G Y
4 . -^nxH
SO2
+
O. Arsenopyrite................. FeAsS H =5.5 to 6 G = 6 to 6.2
Mercury. Hg H =~
Fusi bility
Sublimates As
I. Smaltite. CoAsS H =5 to 6
Residue
Odor
Minerals of Metallic Luster, Metallic Yellow, Bronze or Red in Color
Crystal system: name, composition, hardness and specific gravity
On coal in O. F. and R. F. Residue
Odor
S02
As
Fusi tí'í3 bility si o> s fl
Sublimates
H. Millerite......................... NiS H - 3 to 3.5 G =5.3 to 5.6 T. Chalcopyrite.................. CuFeSa H -3 .5 to 4.1 G =4.1 to 4.3 Ï. Pentlandite.................. (Fe-Ni) S H =3.5 to 4 G =4.6 to 5
Volatile, white
+
I. Pyrite......................... FeS" H = 6 to 6.5 G =4.9 to 5.2
+
O. Marcaeite.................. FeS2 S = 6 to 6.5 G =4.6 to 4.9
I. G old................................ Au ‘. H =2.5 to 3 G=15.6to 19.3
Heated in closed tube
Other tests
Appearance
Red bronze on fresh fracture. brittle with red frae Tarnishes in blue, purple and ture and ignited black tints. Very brittle and with HC1 gives azure usually massive. blue flame oolored in hair-like or Roasted colors borax 1.5 to 2 Sol. aqua, 0. F. red hot, brown needle crystals. Crusts made regia up of radiating needles. cold 2 to 2.5 Sol. HN0 8 Darkens, may Like bondto except Bright-yellow brassy masses and crystals, tarnishing in {residue S) give yellow gray “ fracture " peacock colors. sublimate Fused globule yellow Light bronze-yellow masses re 1.5 to 2 on fracture. Borax sembling pyrrhotite but not O. F. reddish brown attracted by a steel magnet. Cleavage octahedral. Slightly magnetic be Bronze-yellow masses, tarnish Easy Effervesces A little S ing brown. Powder attracted fore fusion (odor H2S) by a steel magnet. Mirror subli Boraxand roasted ma Pale copper-red masses some Partial terial give blue, times enclosed in white metal mate green, brown, suc lic crust. cessively as borax is changed 2.5 Sol. HNOs Fusible subli Fused mass efferves Pale brass-yellow cubes or other ces in HC1 with odor crystals, isolated or grouped (residue S) mate red in crustB or bounding a mass. hot, yellow H2S Also massive globular, nodu cold lar stalactitic. Pale brass-yellow " spear,” 2.5 Sol. HNOs Fusible subli Like pyrite “ cockscomb ” and simple (residue 8 mate red tabular crystals. Often radi hot, yellow ated. Fresh fracture whiter cold than that of pyrite. 2.5
I. Bornite............................ Cu5FeS4 H =3 G =4.9 to 5.4
H. Pyrrhotite................. Fe8 H ==3.5 to 4.5 G =4.5to 4.6 H. Niccolite................... NiAs H =5 to 5.5 G =7.2 to 7.7
Solubility
+
2.5
I. Copper............................. Ou E =2.5 to 3 G = 8.8 to 8.9
Sol. HNOg Blackens (residue S)
Sol. aqua regia
Sol. HN0 2 (green)
i is yel- Golden yellow to pale yellow nuggets, grains and aoaleB or distorted crystals, passing into wire, fern and leaf forms. Malleable. Streak golden yel low to pale yellow. Fused mass is red and Copper red,disseminatcdgrains,. ignited with HCl sheets and irregular masses or gives azure blue groupsofextendedandbranchflame ing crysta ls. M alleable.' Streak copper red and shining.
H is
So >40 feu
Taste
M. Alunogen........ ................. Astringent Al2 (S04) 3 I8H20 H « 1,5 to 2 G =»1.6 to 1.8
Heated on charcôal
O
K}
The fused i low
Heated in dosed tube Reorystallization in a drop of water
loses water be- Much water, S02 and Feathery infusible. Deep SOg at high heat blue with Co. sol.
8
a Appearance White efflorescence or fibrous crusts.
O. EpBomite................... MgS04 7 H20 H =2 to 2.5 G = 1.7
Bitter
M. Copiapite................; . . . . Fe3 (0H)a (S04)s la n ío H =2.5 G =3.1
Metallic, nauseous Fuses, becomes mag MuclrsSia water netic
M. Borax....................... NajB407-f-10 H20 H =2 to 2.5 G = 1.7
Sweetish alkaline
F. «= I to 1.5. Swells and Puffs up. Gives much Unsymmetrical water polygons gives clear glass
Snow white crystals, crusts or por ous masaos.
M. Kernite........................ Na2B40 7 + 4 H20 H =3 G =1.953
Trace of sweetish taste
F. = !. Swells and gives Puffs up; gives much Unsymmetrioal a clear glass water polygons
Tri. Sassolite.................. HgBOj H «l 0 = 1.4
Acid
F. =2. With intumes Water and a little am Six-sided plates and White pearly scales or plates. threads cence to dear glass monia
Like alunogen but pink Water. Acid at high Lath shaped with Co. sol. temperature
Ö H W ►5
Minerals of Non-Metallic Luster and with D ecided Taste (Soluble in Water) Crystal system: name, composition, hardness and specific gravity
I
White fibers or crusts.
«
§ g
w
No recrystallization Yellow scales or granular
Î g
Tri. Chaicanthite.................... Metallic, nauseous Fuses. Reduoes with Swells, whitens. Yields Blue crystals CuS04 5 H20 effervescence to copper water H =2.5 G =2.1 to 2.3 button
Blue glassy crystals, veins and crusts.
co
to Ol
1-26
Minerals of Non-Metallic Luster a»d with Decided Taste (Soluble in Water)— Continued Crystal system: name, composition, hardness a'iid specific gravity
Heated in dosed tube Recrystallization in a drop of water
Appearance
F. = 1 to 1.5. Ignited Much water with Co. sol, pink
0. Nitre................................... Salty and cooling KNO* H =2 G=2.1
F. = 1. Swells, froths, Much water. Acid at Ootahedron. (Three- White fibers or mealy efflorescence. will stain silver high heat six- and four-sided polygons)
M. Kainite.............................. Salty and bitter
F as» easily and if fused Water with soda will stain silver
Rectangles
White to brownish red granular masses.
tt
Su
MgS04KCl+5H20
White to reddish granular masses. Very deliquescent.
With KHSO4 brown Lath shaped vapor
White needles or thin crusts.
Q t
H =2.5 to 3
&
I. Sylvite................................ Bitter KC1 H =2 G = 1.97 to J.99
F. = 1.5
Residue alkaline on moist test paper
Square (cubes)
White or colorless. May be bluish or yellowish red.
H. Soda nitre.......................... Cooling NaNOa" H = 1.5 to 2 G =2.2
F. » I. Deflagrates
With KHSO4 brown vapor
Rhombic outlines
White, pale red or pale yellow masses and crystals with forms and angles of calcite.
M. Mirabilite........... ............. Bitter
Fuses and will stain di Water ver
Lath shaped
White efflorescence or powdery crust.
I..Halite.................................. Salty NaCl H =2.5 G =2.4 to 2.6
F. = 1.5
A little water
Square (cubes)
White or colorless or impure brown, yellow or red masses and crystals with cubic cleavage.
M. Trona................................ Alkaline NaC0g.NaHC08+ 2 H 20 H=2.5 to 3 G =2.1
Fuses easily
Water
Spherulitic
White glistening crusts.
S|
â gs O« OîB 93
I ñ 1 0 p<
yO UO
Ä
G =2 to 2.2
Rectangles
Na2804+iOHaO
H = 1.5 to 2
G = i.5
M IN E R A LO G Y
ot
Heated on charcoal
O. Carhallite.......................... Salty and bitter KCI.MgCl.6 H2O H =l G o li o %
k
Taste
Minerals of Non-Metallic Luster, Tasteless and with Colored Streak Crystal system: name, composition, hardness and specific gravity
H
9
e>
I
M. Azurite.......................... Cu3{0H )2 (C0 2) 2 H »3 .5 to 4 G =3.8 I. Lazurite.......................... Na4(NaS,Al)Al2 (Si04)3 H =5 to 5.5 G =2.6 to 2.9
+• (Separation of silica)
O. Ataeamite....................... Cu2(OH)8Cl H =3 to 3.5 G =3.7 to 3.8
TurnB brown
Other tests
Appearance
flame with H2SOi (con c.). Yellow pt. with ammonic molybdate
Bluish-green to dark blue, often earthy and filling shells, horn, etc. Rarely as colorless or glassy crystals, gradually be coming blue.
Infusible. Blackens. (Blackens) Yields water
Enamel-like crusts, veins, or masses. .
+
(Odor H2S)
+
Chlorite group..................... H = J to 2.5 G =2.6 to 2.9 (Micaceous dark-green min erals such as clinochlore HeMgsAJiSijOis)
Garnierite............................ H2(Ni-Mg)Si0 4 + H20 H = 2 to 3 G =2.3 to 2.8
2 to 2.5. (Magnetic)
Heated in closed tube
(Black)
Yields water
3.5 (White)
Water. Green glow
(Colored)
+
(Separation of silica) + (Green)
Infusible. Blackens. (Magnetic) Yields water 3 to 4 (Copper)
Deep-blue fine-grained masses, usually spangled with pyrite and intermixed with other minerals. Dark-green masses of coarse to very fine scales. Tabular and curiously twisted six-sided crystals and fan-shaped groups which cleave into thin soft pliable b,;t not elastic plates. Abo as a pigment in other minerals. Dark emerald-green masses, often cellular and very crum bly and paler-green masses and crusts. Luster dull.
Deep emerald-green, confused White and red sub aggregates and slender prisms. limates Formerly found as a sand.
1-27
fi
—. Chrysocolla.................. CuSiOa-2 H20 H = 2 to 4 G =2 to 2.3
Fusibility on coal
TABLES
ë 1
+
Insoluble
D E T E R M IN A T IV E
I
M. Vivianite........................ Fe3(P0j) 2 + 8 H20 H = 1.5 to 2 G =2.6 to 2.7
Simple solution
AND
s
There is a residue of jelly
D E SC R IP TIV E
i
S3
In powder boiled with hydrochloric acid There is efferves cence
Minerals of Non-Metellic Luster, Tasteless and with Colored Streak—Continued In powder boiled with hydrochloric acid Crystal system: name, composition, hardness and specific gravity M. Malachite.................... Cu2 (0H) 2C0 2 H =3.5 to 4 G =3.9 to 4
There is efferves cence
Kin
w H
Insoluble
Fuses. (Copper)
Infusible. (.Brown)
Turquois........................ Ala (0H) 8P0 4H20 H =6 G =2.6 to 2.8 H. Iodyrite......................... Agl H =>I G =5.6 to 5.7
Fuses. (Silver)
Sulphur, S........................... H = 1.5 to 2.5 G =2.0 to 2.1
+
O. Orpiment........................ AS2S3 H<= 1.5 to 2 G =3.4 to 3.6
+
+ (Green)
O. Autunite........................ C a (ü 0 2)2 (P0í)2+8H 20 H = 2 to 2.5 G =3 to 3.2 H. Greenockite................. CdS H =3 to 3.5 G =4.9 to 5
+ (Odor H2S)
H. Vanadinite.................. Pb6Cl (VO*)s H<=3 G = 6.6 to 7.'
+ (Residue)
H. Pyromorphite............... Pb6Cl (POs)a H —3.5 to 4 G =5.9 to 7.
+ (Residue)
+
Liznonite............................ FeaOi-Fe2(OH)6 H =»5 to 5.5 G =3.6 to 4
T. CasBiterite...................... Sb Oji H = 6 to 7 G =>6.8 to 7.1
1
+
Heated in closed tube
Other tests
Appearance
Green flame, blue Bright-green radiating fibers or Blackens. crusts, often banded in shades Much water with HC1 of green, sometimes staiactitic. Also dull green and earthy. Rarely, slender crystals. Water. May Green flame, blue Emerald-green needle crystals. with HC1. Fused Fibrous veins and 1 blacken. with soda, stains Acid at high tem silver perature Yellow ppt. as in vivi- Sky-blue to green nearly opaque Biackens. anite. Green flame nodules or veins, with luster Yieldfl of wax. blue with HC1 water C losed tu b e w ith Yellow or yellowish-green, thin Fuses, KHSO4 violet vapor veins or flexible plates or crys orange hot, yellow and globule deep tals. Cuts like wax and is not red hot, yellow cold affected by sunlight. Streak cold yellow. Unchanged by sun Sulphur yellow to brown, trans Fusible subl lucent crystals, irregular brown hot, masses, crusts, stalactites and yellow cold powder. Streak pale yellow. Soluble in nitrio acid Lemon yellow, foliated and Boils. Transpar with separation of eleavable to flexible scales, also granular, and as small ent yellow sulphur crystals. Streak lemon yellow. sublimate
(Arsenical odor. Blue fíame) Easy Fades. (Blaok Yields water and crys talline) Infusible Carmine hot, yellow but cold brown sublimate
Yellow ppt. aBin vivi anite. Borax odor le s s O. F., gree R. F. The coal may show also a variegated tarnish
% tei PS O
S «1
Yellow tabular nearly square crystals and scales and foliated aggregates. Streak pale yel low. Bright yellow coating or inclu sion w ith zin c m in era ls. Streak orange yellow.
With
On coal greenish yel Red, yellow or brown. Sharp low subl. with Bi hexagonal prisms, sometimes Red hot, fiux. With S. Ph. hollow. Also globular masBeB. yellow cold 0. F. amber, R. F. Streak pale yellow. K H S O i.
Yellow ppt. as in vivi- Green, brown or gray. Hexag anite. Greenish yel onal prisms and tapering low subl. on coal groups in parallel position. with Bi flux Also rounded and moss-like aggregations. 5 Blackens, Solution gives dark- Brown cru stB of curved (rhom(Black becomes blue ppt. with po- bohedral) crystals, or massive and magnetic tassic ferricyanide with cleavage at 107°, or gran magnetic) (ferrous iron) ular. Streak pale yellow. Infusible No subli On coal subl. yellow Yellow-brown or black trans or with mate h ot, w h ite co ld , parent to translucent crystals difficulty bright green if ig and eleavable masses with nited with oobalt strong resinous luster, and solution compact fine-grained masses or alternate concentric layers with galena. Streak pale brown. 5 to 5.5 Water. On coal R. F. strong Occurs massive but is best (Black. Reddens ly magnetic known aB yellowish to brown Mag and red needles, scales and netic) velvety crusts. Streak yel low to yellowish brown. 5 W&Sr Much water. Like goethite Brown dull-lustered heterogene (Black. Reddens ous bog ore, cellular staiactitic Mag and pipe-like concretions of netic) rusty brown to nearly biack, often fibrous smooth masses. Infusible S. Ph. O. F. slowly to Brownish red to nearly black yellow, made violet crystals with brilliant luster R. F. often parallel or netted. More rarely massive. Streak pale brown. Infusible On ooa l stro n g ly Brown to red and nearly black. heated and aided D u ll, kidn ey-shaped and by soda or sulphur rounded pebbles. Brilliant gives button and crystals, and disseminated subl. yellow hot, grains. Streak pale brown. white, cold, bluish green if ignited with cobalt solution (Recrystallizes)
I. Sphalerite...................... + ZnS (Odor H2S) H —3.5 to 4 G «3.9 to 4.1
T. Rutile.............................. TiOa H «=6 to 6.5 G =4.1 to 4.2
I (SO2 odor. Biue fíame)
1.5 (Black)
B'. Siderite........................... + FeCOs (Slowly in H = 3.5 to 4 G =3.8 to 3.9 cold acid)
O. Goethite........................ FeO (OH) H = 5 to 5 .5 G » 4 to 4 .4
Fusibility on ooal 3. (Black)
+
s* «a
Simple solution
g
+
0. Brochantite............... CiiBÒ ■3 Cu (OH)a H =3.5 to 4 G =3.9
Minerals of Non-Metallic Luster, Tasteless and with Colored Streak— Continued In powder boiled with hydrochloric acid Crystal system: name, composition, hardness and specific gravity
M. Erythrite................ . Cog (Ab04)2-8 H2O H = 1.5 to 2.5 G =2.9
There is efferves cence
There is a residue of jelly
Simple solution
Insoluble
+ (Light red)
H. Cinnabar...................... H gS
H « 2 to 2.5
G = 8 to 8.2
H. Proustite........................ AgsAßSä H = 2 to 2.5 G =5.6 to 5.7
+
H. Pyrargyrite.......... AgsSbSa H =2.5 G =5.6
Appearance
Volatilizes without fusion
Black.subl., Closed tube with soda Vermilion, scarlet and dark red if m e t a llic m irror brownish-red fine-grained which can be col masses. Crystalline crusts. rubbed lected into visible Streak scarlet. globules. Soluble aqua'regia
r (Garlic odor. Silver) 1
Infusible
+
Other tests
Water
(W h ite
Alai} (Ofi>4
Heated in closed tube
Fuses. (Garlic odor)
subl. Silver)
Bauxite................................ H = it o 3
Fusibility on coal
G >=2.4 to 2.5
B ora x deep b lu e, Pink earthy crusts or powder O. F. and R. F. or crimson fibers. Streak pink to crimson.
Fuses. Soluble HN03. De Scarlet to vermilion crusts or Slight red composed by boil masses. Rare six-sided prisms subl., yel ing KOH and a yel with brilliant adamantine low cold low ppt. by HC! luster. Streak scarlet. Fuses. Subl. As with proustite but Blackish red veins or crusts black hot, ppt. is orange with a brilliant adamantine red cold luster. Red tint stronger in thin layers. Rare crystals. Streak purplish red. Water at high heat
Deep blue if ignited Red to reddish-brown masses with cobalt solution of rounded grains or clay-like. Dull in luster. Streak reddish brow n .
If el
3 (Copper)
H. Ilmenite........................ FeTiOj H • 5 to 6 G = 4.5t o 5
+ (Slowly)
Infusible O. F. with diffi culty R. F.
Solution boiled with tin becomes violet. Fused with soda is magnetic
Infusible (Mag netic)
Dark-blue ppt. with Dull dark red, massive, oolitic, potassio ferrocy- or earthy, sometimes kidneyanide shaped and fibrous. Streak brownish red.
xn H. Hematite........................ 38 FeîOj H =5.5 to 6.5-G = 4.9 to 5.3 «
M. Crocoite......................... PbCr04 H=2.5 to 3 G=5.9 to 6.1
+
(Burns blue l.iK*“ (Lead)
Brownieh-black to rusty-brown plates, grains and masses and thin tabular crystals. Streak brownish red.
Boils, gives Soluble KOH. HC1 Orange-red granular masses of subl. black ppts. yellow flakes. resinous luster and transpar hot, red Soluble HNOa ent crystals. Streak orange cold red. With KHSO4 dark violet hot, green ish cold
In S. Ph. 0. F. and Hyacinth red prisms, R. F. bright green. orange yellow. On coal Bi flux greenish yellow
Streak
Fuses (Lead)
Some water In S. Ph. O. F. amber, Black, brown or red crusts R. F. green. On of minute crystals. Streak coal with Bi flux brownish orange. greenish yellow
H. Zincite............................ ZnO = 4 to 4.5 G =5.4 to 5.7
Infusible (Subli mate)
Blackens
Sublimate ignited Deep red to brick-red adaman with cobalt solution tine masees. Granular or is bright green cleavable. Very rare crystals. Streak orange yellow.
TABLES
0. Descloisite...................... (PbOH) VO4 (Pb, Zn) H = 3.5 G «5.9 to 6.2
D E T E R M IN A T IV E
M. Realgar.......................... AsjSs H = 1.5 to 2 G = 3.4 to 3.6
+
Ignited with HC1, Dark-red to brick-red masses, azure-blue flame Deep-red to crimson isometric crystals, sometimes hair-liko. Streak brownish red, shining.
AND
+ (Brown)
D ESCRIPTIVE
«E
I. Cuprite............................ CU2O H = 3.5 to 4 G =5.8 to 6.1
Minerals of Non-Metallic Luster, Tasteless and with White Streak, and Yielding Reactions on Charcoal with Sodic Carbonate
FUSED ON CHARCOAL WITH
H= W «
a
Black
Colorless ! or white
Brown +
Gray
Yellow +
Red
Green
Blue
+
Solubility
Insoluble
Flame coloration
Blue
S 1.5 to 2.5 G —2 to 2.1
.
+
Zn3COs (OH)« H =2 to 2.5 G =3.6 to 3.8
effervescence
Heated in dosed tube
to w 3 *
a 10
Yellow green (Coal R. F.)
+ SbîOg H =2.5 to 3 G =5.6 +
+
Bright translucent crys Ta^es fire and burns with odor tals and masses or S0 2 powder with resinous or dull luster.
Water. Yellow hot
On coal R. F. heavy Chalk-like masses or white subl. made crusts on other 2ino bright green by minerals. ignition with co balt Bolution
Fuses, partly sublimes
Volatile white subl. W h ite silk y m inute on coal crystals or radiating fibers.
Decrepitates
Bright yellow subl. Simple crystals, often on coal with Bi transparent and color less. White brittle flux masses and compact granular masses of gray color from inter mixed galena.
PbS0 4 H =3 G=6.1 to 6.4
fe +
+
+
H. Vonadinite.................... PbjCl (VOj ), H =3 G = 6.6 to 7.2
+
+
4-
O. Cerussite....................... PbCOs H =3 to 3.5 G =6.5 to 6.6
+
+
green solution
Like anglesite. Also Tabular square crystals Darkens. Decrepitates solution, cooled of resinous luster. d ilu ted boilec with tin is blue
+
Hemimorpbite (calamine) (ZnOH)2SiOs H =4.5 to 5 G =4.3 to 4.5
Sol. with effervescence in hot HC1. Crystals on cooling
Turns yellow then red, cools yellow
Like anglesite
Twinned crystals or in terlaced fibers or gran ular masses, often with
Sol. HNOa
Like anglesite. Also Hexagonal prisms and fuses O. F. and on taperi g groups in porcooling has facets a’lei position. Also rounded and moss-like aggregations.
Sol. with efferves cence and odor H2S
On coal R, F. heavy Transparent to transluwhite B u b l. made e e n t c r y s t a ls and bright green by deavabie masses with ignition with co strong resinous luster. balt solution Compact masses or alternate layers with galena. Barely a white powder.
Sol. with jelly
Water
Like sp h a lerite White masses, the cavi (best if soda and ties lined with crys borax added in ig tals, often showing nition) only ends, usually par allel, forming ridges. The fracture shows the crystals like par allel fibers.
Sol. with efferves cence
Yellow hot, if pure
Like sphalerite
Porous, oellular masses. Crusts with smooth rou n d ed su rfa ce s. Occasional drusy sur faces, the crystal ends being three-faced.
TABLES
H. Bmithsonite............. .. . ZqCOj H =5 G =4.3 to 4.5
+
3. Ph. O. F. amber, Sharp hexagonal prisms, R. F. green sometimes, hollow. Also parallel groups and globular masses.
D E T E R M IN A T IV E
I. Spbaler'te...................... ZnS H =3.5 to 4 G —3.9 to 4.1
With KHSO4 yellow to red hot, yellow cold
AND
SODIC CARBONATE YIELDS:
H. Pyromorphite.............. Pb8Ci (PO|)» H =3.5 to 4 G =5.9 to 7.1
+
Sol. HNOj to yellow solution
D ESCRIPTIVE
FUSED ON CHARCOAL WITH
;
I
PbMoOi H =3 G = 6.7to 7
Appearance
Yellow fusible. Sublimate brown hot
6 0
Other tests
M IN ER A LO G Y
SODIC CARBONATE YIELDS:
1
The color of the mineral is: Crystal system: name, composition, hardness and specific gravity
CO
Minerals of Non-Metallic Luster, Tasteless and with White Streak, and Yielding Reactions on Charcoal with Sodic Carbonate— Continued
I
The color of the mineral is: Crystal system: name, composition, hardness and specific gravity
Flame coloration
Solubility
H. Willemite...................... ZdìSìOì H =>5.5 Q =3.9 to 4.2
+
+
T. Caasiterite.................... SnC>2 H = 6 to 7 G = 6.8 to 7.1
+
I. Cerargyrite.................. AgCl H = ! to 1.5 G - 5 to 5.5
Heated in closed tube
Other tests
Appearance
Sol. with jelly
Like sphalerite
Insoluble
On coal with soda Crystals with brilliant non-volatile eubl. adam antine luster, made bluish green disseminated grains by ignition with and rounded heavy cobalt solution pebbles dull and often with radiating struc ture.
Granular masses inter mixed usually with black and red grains. Rarely large reddish or brownish crystals. Luster resinous.
Insoluble
With KHS04 On coal acrid odor T h in cr u s ts w h ich yellow hot, and silver button darken in sunlight and white cold, cut like wax with shin violet in sun ing surface after cut ting.
3 8 c I. Embolite...................... Ag (Cl-Br) H = 1 to 1.5 G = 5.3 to 5.É
Insoluble
With KHSO4 Like cerargyrite dark red hot, dark yellow cold, dark green in sun
H. Siderite........................ FeCOj H =3.5 to 4 G =3.8 to 3.9
Emerald green
Slow effer vescence in cold acid
+
CaS04 2 H20 H = 1.5 to 2 G=2.3
+
+
+
P m
Soluble. Rccrystallizes on evaporation
Whitens. Yields water
10
1 BaS04 H =2.5to3.5 G=4.3to4.6
+
+
+
+
+
+
Insoluble
Like cerargyrite.
Blackens. Witb soda on coal, E nam ei-like cruets, Yields water a copper button v e in s or c o m p a c t masses. Never crys tals. Black and magnetic
red
On coal becomes Compact, fine-grained black and mag and cleavable masses netic and rhom bohedrai cu rv e d c r y s t a ls . Cleavage angles 107°.
Soft, colorless or slightly tinted masses, which may be scaly, silky fibrous or compaot or may be masses and crystals, cleaving in three direction^ to a rhombic plate of 66°.
SrS04 H =3 to 3.5 G =4
••8
gs
CaS0 4 H » 3 to 3.5 G =2.9 to 3
+
+
+
Insoluble
Crimson tale and fibrous, lam ellar and granular masses. Cleaves in three directions to rhombic plates of 76°.
+
+
+
+
Soluble. White ppt. with BaClj
Yellowish red
Partial
Violet. (Color Screen)
Water at high heat
Blue b y ignition 1 with Co. solution small cuboids, usually mixed with hard, sili ceous material.
Yellow
Water and green glow
Blue in fine powder I
gr a in e d m a s s e s . CleaveB in three direc-' tions at 90°.
02tx, H«
K(A103) (S04>2+3H20 H =3.5 to 4.5 G =2.6 to 2.7
Na* (NaSjAl) AI2 (Si04)$ H = 5 to 5.5 G =2.4
§
fib r o u s . Crystals common. Cleaves in three directions to rh o m b ic p la te s of 78ya°.
02
oB
ICO
H3
Yellowish green
H® U|z g«
W
+ jelly and odor HjS
I h3
spangled with pyrite and intermixed with other minerals. CO Cn
Minerals oi Hon-MrtdUc luster, Tasteless end w itl WUte Streak, and Yielding Ho Tests with Sodic Carbonate
è
Gray
+
+
+
+ AlNa8F6 H = 2.5
Colorless or white
Red
+
1 g
Brown
O
Yellow
a
+
Solubility
Heated in Flame coloration closed tube
Slight in EEC!
Crimson
Soluble
Yellow
G = 2.9 to 3
1 Ü w
+ CaFg H =4
+
+
+
+
orange
G =3 to 3.3
o H . H4R2AI2 (SiOs>6 + 4H20 S? G = 2.lto2.2 4o* H = 3 .5 to 4 H
+
sCO
<8 (CaNo2) Al (Si04)8 6 H20 M H=4.5 G ==2.0to 2.1 CO W
+
Soluble with residue
+
+
Soluble witl lumps jellj
+
+
+
Hi4K 2Ca8 (Si0a)i6 9H 20 H =4.5 to 5 G =2.3 to 2.4
Appearance
Masses of ooarse or fine scaleB with easy cleavage into thin ner plates. Etches tube Blueif ignited with Translucent masses resem bling watery snow. Rarely small six-sided monoclinic crystals nearly cubes. Phosphor-
+
+
Other tests
Wifch KHSO4 etches tube Water
Transparent cubes and masses of glassy luster which cleave in four directions at angles 70° 31'. Color usually bril liant. Sometimes banded.
M IN ERA LO G Y
ËÜ M. Lepidolite........................ (KLi)jAl (Si08)8 S H —2 to 2.5 G ■=2.8 to 3.2
Blue
Crystal system: name, composition, hardness and speoifio gravity
Purple or violet
The color of the mineral is:
Swells greatly dur Sheaf-like groups or many small crystals forming a ing fusion crust or lining. One easy cleavage giving symmetrical pearly face.
Much water Intumescence dur Groups of small rhombohedral crystals which are nearly ing fusion cubes.
Tabular or “ cubic” or pointed Soluble witl Pale viole Much wate Exfoliates durinj lumps jell}r (Color cence. Occasionally lamellar. Screen) One easy cleavage.
1S
+
+
+
+
+
+
Bubbles in fused Coarse thick crystals with material octagonal or square crosssection. Cleavage angles 135° or 90°. Cleavages faint ly fibrous. More rarely mas sive columnar or fiae-grained aggregates. Masses and crystals with two easy cleavages, nearly but not exactly 90°. Often show parallel striations. Some times opalescent.
Insoluble Partial
Yellow
Insoluble
Crimson to Water and Momentary blue- Cleavable masses and rough yellowish etching of green flame with crystals. One easy cleavage. red tube h 2s o 4
Soluble
H. Tourmaline...................... R ibBî (SiOs)< H = 6 to 6.5 G «=2.8 to 2.9
Insoluble
Green with KHSO* +CaF 2
After ignition die Prismatic crystals often hemisolves leaving morphio and roughly tri jelly angular in cross-section.
I. Boracite. H o>7
Soluble
Yellowish green
Violet if ignited Minute glassy crystals. with cobalt solu tion
G =2.9 to 3
A little water
After fusion dis Lining cavities as smooth solves leaving rounded cruets or as sheafjelly like groups of tabular crys tals. Sometimes in barrel shaped crystals.
TABLES
O. Prehnite........................... HaCaîAla (SíOí)j H = 6 to 6.5 G =2.8 to 2.9
D E T E R M IN A T IV E
Tri. Amblygonite.............. Li (A1F) P 0 4 a =6 G =3 to 3.1
Yellow
AND
fri Plagiociase...................... nNaAlSiaOfi-fmCaAläSiiOg K = 5 to 7 G =2.6 to 2.7 (Albite).......................... (Labradorite).................
Imperfeot
D ESCRIPTIVE
T. Wernerite Group. . . . Silicates of NaCaAl H =*5 to 6 G =2.7
1-37
J_3g
Minerals of Non-Metaliie Luster, Tasteless and with White Streak, and Yielding No Tests with Sodic Carhonat^ -C on tin u ed The color of the mineral is: Crystal system: name, composition, hardneBs and spedfic gravity
M. Colemanite................ Ca2Bfi0 n -5 H 2O EE“ 4 to 4.5 G =2.2 to 2.3
í?tG oïg y* 0 O. Natrolite..................... Na2Al;;S¡aOso+ 2HjO Qtn H <=5 to 5.5 G =2.2 SH «Of* <5 I. Analcime..................... M NaAl(Si03)2 -H20 Cfl H =5 to 5.5 G =2.2 to 2.3 g M. Datolite......................... g Ca (B0H)8i0 4 H =5 to 5.5 G “ 2.9 to 3
t
+
NagAIgSisOsi H =5.5 to 6 G =3.2 to 3.6
10 3 Ö 10
3
Pyroxene (diopside).............. CaMg (SiOg) 2 H =5 to 6 G =3.2 to 3.6
+
M. Amphibole (tremolile) . .. CaMga (Si08) 4 H =5 to 6 G =2.9 to 3.4
+
+
+
+
+
Reddish yellow
Much water Green flame with Nodular masses of silky fibers. KHSO«andCaF2 Decrepitates be fore fusing
Water
Soluble with Yellow jelly
Water
Soluble with Yellow lumps jdly
Water, but Becomes opaque Trapezohedral crystals usually forming a lining. •Hardy before fusion keeps granular. luster
Soluble with Green jolly
Water at high heat
Slender prisms with square cross-section and fiat pyra mid at end.
Brilliant small highly modi fied glassy crystals lining a cavity, also porcelain masses. No easy cleavage.
+
Soluble with Yellow jelly
+
Insoluble
Usually prismatic crystals with eight-sided cross-sec tion and angles between alternate faces 90° or 87°. Cleavage angle of 87°.
+
Insoluble
Fibrous and columnar, often radiating. Also crystals with cross-section, a rhomb of !24° or six-sided section. Cleavage at 124°.
Blue if ignited with Translucent masses and coarse cobalt solution hexagonal crystals with pecu liar greasy luster. More rarely highly modified small white crystals.
o
1-4
Masses and crystals with two easy cleavages, nearly but not exactly 90°. Often show parallel striations. Some times opalescent.
o
s
to 3 03
(Anorthite) CaAJ2Si20g___
i to
(Oligodase) Aba to 6 An -..
+
+
+
+
+
Soluble witb jelly
+
+
Insoluble
Yellow
Usually pure white, often granular with curved cleav age surfaces. White ppt. with H2S0 4
Highly modified glassy crys tals or grayish-white larger crystals
Yellow lions. Sometimes spangled (Suasione).
i (Labradorite) AbAnj to s- •
+
Beautiful play of color.
LiAl (SíOj)í H =6.5 to 7 G = 3.1 to 3.2
+
+
+
Insoluble
Sprouts and be comes opaque deavage at 87°. Often sepa during fusion rate in broad plates (bisect ing cleavage angle). Often striated and etched or rough ened.
1-39
Î
Crimson
TABLES
(Albite) NaAlSisOg...........
D E T E R M IN A T IV E
Tri. Plagioclase..................... nNaAlSisOa+ mCaAl2 Si20g H H = 5 to 7 G =2.6 to 2.7 «Il
AND
o
o H
Highly modified crystals with one easy deavage, deavable or fine-grained compact “ porcelain-like" or loose, chalk-like masses.
Green Soluble (with crys tals on cooling)
D E SCR IPTIVE
01
Other tests
§1 <3 8
M IN E R A LO G Y
« O á o
Heated in Flame coloration dosed tube
Solubility
Minerals of Hoa-Metafflc Luster, Tasteless and with White Streak, and Yielding Ho Tests with Sodic C&xbomte— Continued è
The color of the mineral is: Crystal ayatem: name, composition, hardness aad specific gravity
Solubility
+
M. Sphene............................ CaSiTiOe H =5 to 5.5 G =3.4 to 3.5
+
Pyroxene............................... RSiOj. Many varieties (Augite) (R « CaMgFeAl) H = 5 to 6 G =3.2 to 3.6 M. Amphibole RSiOg H = 5 to6 G =2.9 to 3.4 (Aotinolite)........................ Ca (MgFe)a (SiOa)4
+
Soluble slowly
+
Insoluble or nearly
Partially soluble
M. Epidote..................... Caa (Al-Fe)2 (AlOH) (SiO<)8 H = 6 to 7 G =3.2 to 3.5
Insoluble or nearly
T. Idocraae (vesuvianite).... CaeAlj (OH-F) (Si04)c H =6.5 G =3.3 to 3.4
Soluble with white residue
+
+
Insoluble or nearly
+
Water at high heat
Insoluble
After fusion will Imbedded crystals, often gelatinize nearly spherical or in druses and granular, lamellar and compact maeses. Also found in alluvial material as rounded grains.
53w
wo
O. Talc............ HîMgj (SiO,)4 = 1 to 1.5 G =2. 5 to 2.9
+
+
(Clinoohlore)...................... (HgMg&AljSiaOjs) H = Ito 2.5 G =2.6 to 2.9 +
Water
Blue if ig n ited Radiated folia or fibers and with cobalt solu compact masses. Smooth tion and aoft like talc.
Insoluble
Water
Pink if ign ited Foliated compact and fibrous with cobalt solu maeses with soapy feeling. tion The foliated talc cleaves into non-elastic plates.
Milky solu tion with conc. H2S04 Like pro chlorite
Much water
Sol. with jelly
Water
Much water
of coarse to very fine Tabular and curiionsly twisted six-sided crys tals and fan-shaped groups which cleave into thin, soft pliable but not elastic plates. Also as a pigment in other minerals. Pink if ig n ited Soft, compact, smooth feeling with cobalt solu' masses of very light weighs. Rarely fibrous. tion
1-41
Sepiolite........................ HfMgîSiaOio H = 2 to 2.5 G = 1 to 2
Partial
TABLES
M. Chlorite Group (Prochlorite)...................... Hg (Mg, F0)tAljSiaOio H>=l to 2 G =2.8 to 2.9
After fusion will Prismatic crystals, the crossgelatinize section often showing a tri angular prism. Often the color is different at opposite ends or center and outer shell. Also radiating aggre gates and in compact masses.
Green with KHSO4 • CaF¡¡
D E T E R M IN A T IV E
Pyrophyllite.......................... HAI (SiOj)* H = 1 to 2 G =2.8 to 2.9
insoluble
AND
H. Tourmaline.................... RisB2 (Si06>4 H = 7 to 7.5 G =3 to 3.2
After fusion will Square and octagonal prisms gelatinize and radiated columnar or granular masses 01 compact resembling jade. D E SCRIPTIVE
?tn I. Garnet............................... Hoi R3R2 (Si04)3 H =6.5 to 7.5 G = 3 .1 to 4.3 (most varieties)
Appearance
Bladed non-terminated crys tals, divergent fibers and granules. Crystals six-aided crosssection, with angles 124° and 116°, also fibrous and compact masses. Some times with luster of horn. After fusion at Foliated aggregates some tracted by mag t im e s w it h p e c u l i a r “ Schiller” or pearly effect. net Borax, 0. F. ame Fine-grained or cleavable masses and disseminated thystine grains, often coated with a black oxide. Sometimes in crystals. After fusion will A secondary mineral often Water at with the original mineral as gelatinize high heat grains or needles. Less fre quently in distinct crystals.
Insoluble or nearly
O. Hypersthene............... (Mg-Fe) SiOj H =5 to 6 G =3.4 to 3.5 Tri. Rhodonite................ MnSiOa H = 6 to 6.5 G =3.4 to 3.7
Other teats
May become S. Ph. O. F. slowly Wedge-shaped or tabular soluble. Undis- crystals, with adamantine yellow solved portion luster. Also massive. Easy milk white, R. F cieavageB give monoclinio violet Usually eight-sided with angles between alter nate faces 90® and 87°. Cleavage angle 87°.
Insoluble
(Hornblende). . . . CaMgFeAl, etc
O' K
Heated in Flame coloration dosed tube
Minerals of Ron-Metallic Luster, Tasteless and with White Streak, and Yielding No Tests with Sodic Carbonate— Continued
M
Black
+
Colorless or white
+
Red
Brown
+
Gray
Yellow
(HK) AlSi04 H = 2 io 2.5 G « 2 .8 to 3
Green
Blue
The color of tue mineral is: Crystal system: name, composition, hardnesB and specific gravity
+
Flame Heated in coloration closed tube
Solubility
even in H2SO4
high heat
like prochlorite
high heat
Like proohlorite
high heat
Other testB
Plates and mosses of scales and crystals, often large and rough, with rhombic or hex agonal cross-section. Luster pearly, cleavage very easy into thin elastic plates.
CO
+
(H-K )2 (Mg-Fe)2 ‘ AI55(SÌO4) 3 coco H =2. 5 to 3 G =2.7
+
O
20
+
(K-H)3MgiAl (SiO^s H =2.5 to 3 G =2.8 oB
+
H4Mg88Ì208 H =3 to 4 G =2.5 to 2.6
BS
+
+
+
+
+
+
Water residue
m2
ÖS
+
SrCOg M
»
to ti
H =3 to 3.5
G =3.7
CaSiO* H =4 to 5
G =2.8 to 2.9
CaW04 H =4.5 to 5
G =5.9 to 6.1
+
+
H. Apatite.................... Ca6 (Cl-F) (P04)3 H “ 4.5 to 5 G =3.2
+
+
+
+
+
+
+
+
+
+
Pale red
Fibrous to compact masses. Rarely tabular crystals. Usu ally intermixed with calcite.
Pale red
S. Ph. O. F. color Very heavy masses with resi
yellow resi due made blue by tin
- f Soluble
o coai O. Enetatite................. (Mg-Fe)Si08 g g H =5.5 G «3.1 to 3.3 lù Orthoclase...................... KAlSisOg H =6 to 6.5 G =2.5 to 2.6
ß
Insoluble or nearly
gS
Insoluble
gi
H. Beryl................................ BejAlî (SiOj)g H »7.5 to 8 G =2.6 to 2.8
+
+
Insoluble
Insoluble
£0
&
O 8 h
Pink or brownish Compact masses with little red if powder ig luster and smooth somewhat nited with cobalt greasy feel, often with veins solution of silky fibers or foliated. Sprouts and glows Masses of parallel or radiating intensely during imperfect needle crystals. fusion More rarely fine granular.
Soluble
+
Rough prisms with hexagonal or rhombic sections. Also disseminated scales. Cleaves easily into thin elastic plates.
Effervesces Crimson in cold di lute acids
withC0 2 -F-S0 4 H =2-5 G »2.6-2.9
Hg .Ha H. Tourmaline.................... R 18B2 (Si06)4 H =7 to 7.5 G =3 to 3.2
Scales or aggregates. Rarely large sheets or pseudo hex agonal crystals cleaving eas ily into thin elastic plates. Luster pearly.'
jelly
Collophano (am orphous). . . essen tially C b j P î Os • H2O
Appearance
less to milk nous luster. Square pyramids white. R. F.deep and drusy crusts. blue
Yellowish red. Mo mentary green with H2S0 4 Yellowish Water red. Mo mentary green with HjS04
Solution added to nitric solution of ammonium molybdate g iv e s bright yellowppt.
Green with KH804 CaFi
Ü GO
Yellow ppt. with Usually massive and without HNO3 and am- form. May be o 8litio or monium molyb- show bone structure. date Like serpentine
Violet (Color screen)
Usually hexagonal prisms. Luster of oiled glass, dull if altered. Also compact, dull, massive bone phosphate.
I ►d
Lamellar to fibrous masses, often with pearly iusierMaeeea and crystals which cleave in two directions at exactly 90°. Except in the variety microcliae the sur faces . resulting are not grooved. Sometimes opales cent.
After fusion will Prismatic crystals, often gelatinize showing a triangular prism. The color may differ at op posite ends or center and outer shell. Also radiating aggregates and in compact Often becomes Hexagonal prisms, from mere white on fusion threads to several ieet in length. Sometimes also in columnar or granular masses.
Ü
h3
TJÌ
X
09
à Minerals of Non-Metallic Luster, Tasteless and with White
Streak, and Yielding N o Tests with Sodic Carbonat*-C m tinued
The color of the mineral is: Crystal system: name, composition, hardness and specific gravity
8
Si s '!
4> « II
Flame Solubility coloration
fi
O to ag KM
ps
5
5
Soluble
M. Aluminite.................. Al^SOu 9 H20 H = 1 to 2 G = 1-6
o ff wt> —Bauxite........................... If) A120 (OH)* O jcn H « l t o 3 G = 2.4 t o 2.5
I
Other tests
Appearance
o £
oj
A M ü
Heated in closed tube
Soluble slowly
+
ù B oh « Ö M. Gibbeifco.. WE Al(OH)8 G =2.4 Q ~ H=2.5 to 3.5 CO(M on h K O. Andalusite.................. (Chiastolite) AljSiOj nin H =4 to 5 G =2.1
Dull day-like or mealy Greasy feel.
Insoluble
Water
Often plastic with water
Insoluble
Water
Often swells in Often occurs in soapy or waxlike masßes of day. water
Soluble
Water
Exfoliates on heating
M. Kaolinite... ■ H4Al2Si20s G =2.6 H = 2to 2.5 M. Montmorillonite.......... (MajCa) 0, A120 8 •5Si02•NH20 H = I to 2 0=2+
Rounded chalky masses with Much acid Infusible with peculiar, harsh (meager) feel. soda but mass water. Odor S02 will stain silver Masses of rounded grains Water at May become (pisolites or oiiSitea) or high heat magnetic in earthy or clay-like. No R. F. luster.
Sd
£ o
%
Small stalactites or thin, smooth crusts, with in ternally fibrous structure. Rarely in small crystals. Coarse, rounded prisms. Often superficially black. Cross-sections show a cross or checked figure.
Insoluble
§
A Tri. Kyanite............................. WK Al2SiOs HO Q m H = 5 to 7 G =3.6 to 3.7
+
+
Insoluble
Triclinio blade-like crystals and blade-like masse.», cleav ing parallel largest face. Col or deeper along center.
Leucite...................................... KAI (SiOi)2 H =5.5 to 6 G =2.4 to 2.5
Soiuble Violet with res (Color idue screen)-
Translucent nearly spherical crystals and grains in vol-canio rocks.
O. Sillimanite................... Al2SiO* H = 6 to 7 G =3.2
Insoluble
Thin, almost fibrous prisma and tough fibrous aggre gates.
O. Andalusite............................ Ai (AIO) S1O4 G =3.1 to 3.2 g o H =7 to 7.5 «ÉJ O. Dumortierite........... .......... 8 A120 î •B2O3•6 SiOî-HüO g s H =7 G =3.26 to 3.36 05ÎH tan Topass........................................ ëg AliîSigOjjFjo H=8 G =3.4 to 3.6 esBH
Insoluble
oS
§0 a®
So
g s go <0
fo rh ¿2 «
feto
2S SS L_ 0
+
InedîîiSë
Insoluble
Coarse, nearly square prisma or tough, columnar or gran ular masses. Water
Blade-like or fibrous crystals.
03 o w h-t ►tf
Ö H
y
W
I
Heated in open Glassy crystals with one easy tube with fused cleavage. Also columnar S. Ph. etches aggregates, and water-worn orystala in alluvial deposit.
g
GO
k
r“
Minerals of Non-Metallic Luster, Tasteless and with White Streak, and Yielding N o Tests with Sodic Carbonai^-Continued The color of the mineral is: Crystal system: name, composition, hardness and specific gravity
• I. Spinel............................... 9a H = 8MgAlgOj G =3.5 to 4.5
+
aiO Hu
+
w
S3
i
IB
O. Chrysoberyl.......................... BftAlgOi H =8,5 G =3.5 to 3.8
ii is
+
+
+
+
+
+
H. Corundum.......................... AI2O8 HÜO H = 9 G =3.9 to 4.1 ÖM« WfM (Sapphire) or (Ruby).
+
+
£ §g &|g hm
Flame Heated in Solubility coloration closed tube
+
+
Often changes Simple or twinned octahedral color on heat crystals and rolled pebbles. ing
Insoluble
Usually pseudohexagohal crystals or pebbles. Emerald green crystals by transmitted light are purplish red; some pebbles show an internal
Insoluble
Coarse crystals or masses with partings in four directions at 86° and 57°, or granular, slightly translucent.
Insoluble
Color changed Transparent to translucent, usually in crystals and of by heating fine colors.
O. Aragonite.................... CaCOg H «3.5 to 4 G «2.9
+
+
+
+
+
+
..
+
+
H. Dolomite.............................. CaMg (COa)a H =3.5 to 4 G «2.8 to 2.9
+
H. Magnesite.......................... MgCOg H ==3.5 to 4.5 G =3 to 3.1
+
H. Rhodochrosite.................. .. MnCOs H =4.5 G =3.5 to 4.5 M. Monazite............................. (Ce-La-Di) PO* H =5 to 5.5 G =4.9 to 5.3
Opaque, granular corundum, intimately mixed with hemaI tite or magnetite.
+
(Emery).
+
+
Orange Lumps rapidly, red effer vesces in cold dilute acid
Unchanged when boiled with cobalt solution
Like cal Orange cite red
Becomes lilac if Simple or pseudohexagonal boiled with co crystals. Also columnar and balt solution needle masses, oolitic, stalactitic and coral-like. Two easy cleavages with angles near 120° (116°, 122°).
Lumps Orange slowly, red effer vesces in cold di lute acid
Pink if ignited Curved rhombohedral crys with cobait tals, or coarse to fine-grained solution masses. Cleaves in three di rections to rhombohedron of 106°,
Effete..
Like dolomite
vesces only in warm acid +
Appearanoe
Insoluble
g«
H. Caloite........................ CaCOs H =3 G =2.7
Other teste
Crystals of many which cleave in three direc tions to rhombohedron of 105°. Cleavabie, coarse and fine-grained, fibrous and loosely coherent masses. Crusts, stalactites.
Compact, dull nodules or veins in serpentine. Shell like fracture. Rarely cleava ble.
Like do!o‘ mite
Darkens on ig Rhombohedral crystals often nition. Borax, with curved edges cleavable O. F. amethys and granular masses. Some tine times as a crust.
Soluble Momen white tary residue green with H2SO4
Yellow ppt. if Translucent grains in some solution added sands and small imbedded to nitric solu resinous crystals. tion of ammo nio molybdate,
Ü
H co
I H3
§ I
I F a Ui
£
Minerals of Non-Meteliic
■p
with White Streak, and Yielding N o Tests with Sodic Carbonate— Continued
Tasteless
The color of the minorai is: CryBtal system: name,composition, liarfiiiPRR and specific gravity
flame Heated in Solubility coloration closed tube
& 11 8*
Sol.HNOg Green (Cu)
Turquois.......................... A h (0H)iP0iH20 H =5 to 6 G >=2.6
ria: Mg
M. Chondrodite.................. HîMgiaSigOstF4 H =6.5 G ==3.1 to 3.2
+
O. Chrysolite....................... wen (M(tFe)2Si04 H=6.5 7 G =3.3 to 3.6
$
+
Opal................................... SiOînHjO H =5.5 to 6.5 G = 2 .1 to 2.2
+
Chalcedony...................... Si02 H =6.5 G «2.6
Whitens on heating
SiOj
H =7
+
+
+
+
+
+
+
+
+
Insoluble
In S. Ph. R. F Crystals with brilliant luster often parallel or netted. gives violet More rarely massive.
Insoluble
Translucent crusts and cavity linings with smooth rounded surfaces, often in concentric layers with wax-like luBter. Never in crystals. _
Glassy hexagonal crystals and glaesy shapeless material be tween crystals of other min■erals. Also nearly opaque material,- containing much iron and alumina.
Insoluble
Crystals only.
T. Zircon.......................... ZrSi04 H=7.5 G =4.7
+
0. Staurolite............................. Fe (A10) 4 (A10H) (SÌO4) H =7.5 G =3.6 to 3.7 H. Tourmaline........................ Rl8B2(Si06>4 H = 7 to 7.5 G =3 to 3.2
+
Insoluble
Glows intensely Sharp-cut square prisms, long on or short, usually imbedded in the associated mineral. Luster usually adamantine or greasy. Also rounded pebbles.
Insoluble
+
+
Insoluble Green with KHSO4 CaF2 Insoluble
A little water
Prisms often twinned, or in threes, crossing at 90° and 120°. Surfaces bright if un altered, Glassy hexagonal prisms dif ferently faced at the two ends. Cross-section often suggests a triangle. In powder is Crystals often rounded with burned to CO2 luster suggesting oiled glass, and cleavage in four direc tions at 70° 31'.
TABLES
I. Diamond...................... C H = 10 G 0.3.5
+
§
D E T E R M IN A T IV E
Insoluble
tr4 O
AND
sS
+
Slowly soluble Translucent veins or lining A little in caustic al with internal color reflec water; tions, or without “ opales kali becomes cence” and with waxy luster, opaque and ehell-like fracture. Also dull like pumice and like d r o p B of melted; '
G »2.6
I. Garnet (Ouvarovitt)............. CajCrj (Si04) 3 H =7 G »3.1 to 4.3
E« SSS
+
Transparent to translucent granular masses or glassy grains, or sand.
2
D E SC R IP TIV E
EL Quartz........................
+
+
Nearly opaque material with wax-like luster found filling cracks and cavities in igne ous rocks.
Sol. with jelly
Ss
+
Like monazite
H.iated in open Compact masses, dissemi tube with fused nated grains and crystals of S. Ph. etches great complexity.
S'S
T. Rutile............................ 2 BB H =>6Ti0 to 6.5 G »4.1 to 4.2 £2
Appearance
Sol. with jelly
Insoluble
+
Other tests
1-49
1-50
M IN E R A L O G Y
MINERAL SUBSTANCES NOT EASILY DETERMINABLE BY A SCHEME The following mineral substances of economic importance have not been included in the determinative tables, some because they lack fixed characters, others because their characters are list in those of their associated substances and others because they occur only in one known locality. Amber, once the most prized of gems, now used sometimes in jewelry, oftener as a mouthpiece for pipes, is a name given to those fossil resins which contain succinic acid and were derived from a particular extinct species of pine. The amber of the Baltic Sea and the Sicilian amber are the most valued. Color, garnet red, reddish, yellow, brownish, sometimes with bluish fluorescence. Luster resinous, streak white, H » 2 to 2.5. G = 1.096. Melts quietly at 125° to 150° C. and gives off a choking vapor. Asphalts are rather indefinite mixtures of hydrocarbons and their oxidized products. They vary from thick, highly viscous liquids to solids, are generally black in color with pitch-like luster, and bum easily with a pitchy odor. They are slightly heavier than water. Examples: the pitch lakes of Trinidad and of Bermudez, Yenzuela; the manjak of Barbados; the elastic elaterite of Derbyshire, England; the albertite of New Brunswick, and the gilsonite of Utah. Sandstones and limestones impregnated with asphalt occur in many localities. Brucite Mg(OH)a. A white, compact, flnely-crystalline mineral, with slightly greenish tint. Soluble in dilute HC1, yielding tests for Mg; also yields water in closed tube. Found in a large deposit on western sitie of Paradise Range, Nevada, associated with magnesite and dolomite, along a contact of granite with a magnesite-dolomite series. Other forms, of non-commercial importance, sometimes associated with serpentine, are apt to be micaceous or fibrous. Camotite, 2 U0 jV20 sK20 -3 EfeO (?). A .canary yellow, pulvurulent mineral, in minute scales, filling the interstices of sandstone in several counties in Colorado. Rarely compact and wax-like. It contains radium, and is an impure vanadate of uranium and potassium, or uranium and lime, or both. Is a commercial source of radium, uranium, and vanadium. Clays are mixtures of mineral fragments, due to rock decay. They are usually plastic when wet, can be molded, and harden on heating. By analysis they are principally silica and alumina, with some iron oxide and small amounts of other elements. Mineralogicaliy they contain hydrous silicates of alumina, free quartz, and varying amounts of many other minerals. In origin they may have resulted from decay in place (residual clays) or may have been transported by water, ice, or wind (sedimentary clays). The most important clays are: Kaolins. White-burning, residual clays, often not plastic, approaching kaolinite in composi tion, but not necessarily composed chiefly of that mineral. They are the basis of white wares and porcelain, etc. Ball clays. White-burning sedimentary clays. They are highly plastic and are added to kaolin to give plasticity. Fire clays. Either sedimentary or residual clays, which stand high degrees of heat without fusion. Composition very variable and apparently best with little free silica, lime, magnesia, or Fuller’s earth. A montmorillonite-bearing clay, greenish in color when moist. Is a natural adsorbent for coloring matter in oiL Stoneware clays. Clays sufficiently plastic and tough to be turned on a potter’s wheeL Terra-cotta days. Usually buff-burning clays, with low shrinkage and dense-burning character. Sewer pipe and paving-brick clays. Vitrifiable, high in fluxes. Brick clayB. Low-grade clays, with considerable plasticity, which harden at a comparatively low temperature. Slip clays. Melt at a comparatively low temperature and form a glaze. Paper clays. White clays free from sand; used for mixing with pulp fiber. Bentonite. Composed essentially of the mineral montmorillonite, usually formed by alteration of volcanic ash. Many bentonites swell in water. Some bentonitic clays extensively used for clarifying oiL Diatomite. An extremely light porous, white, mass of microscopio, opaline, organisms (diatoms), chiefly silica, but yielding much water in the closed tube. Used as a heat insulator, also for brick or in filtration. Gilsonite. An asphaltite. Sp gr = 1.01 to 1.10; melting point, 230® to 400° F; found in veins in NE Utah. Was probably distilled by heat from the underlying Green River shale. Used for varnishes and Japans, printing and rotogravure inks, and in various commercial products; 32 227 tons reported mined in 19S5. Grahamite or Glance Pitch. An asphaltite. Sp gr of about 1.15 or more. Largely mined ia Cuba, where found in sedimentary and serpentinous rocks. Formerly mined in Pushmatoka Co. Okla, and Ritchie Co, W VaKieserite (MgSOj - f H 2O) is the source of Epsom salts, and an important source of magnesium oxide and basic carbonate (magnesia alba). It occurs at Stassfurt, Prussia, as about'one-fifth of a layor 190 ft thick, chiefly halité and carnallite, and as one of the constituents of the overlying mixed salts. Exposed to the air it becomes epsomite. After removal of associates there remains a mass slowly soluble in water and easily fusible. H =» 3 to 3.5, G = 3.5. Rarely orthorhombic crystals. Livingstonite (HgSbiS?). Found in Mexico, at Huitzuco and Guadaloazar and said to have been used as a source of mercury. It resembles stibnite in appearance, has metallic luster, lead« gray color, red streak, H = 2, G => 4.81, and occurs in groups of slender prismatic crystals.
IN D E X
TO
D E T E R M IN A T IV E
TABLES
1-51
_ Blottramite (CuPtygVjOio-S HjO). The vanadium of commerce was formerly obtained from thin, blackish incrustations of mottramite upon the Keuper sandstone, Cheshire, England. Streak yellow, H = 3, G = 5.9. • .Ocher, commercially, is a golden-yellow intimate mixture of clay with 20% or more of hydrated ferric oxide. Mineralogists use the name also for pulverulent yellow iron oxide (xanthosiderite) and for pulverulent red hematite. Ozocerite, or mineral wax, is essertiaUy a paraffine, colorless to white when pure, but oftener greenish or brown, and possessing all the properties of beeswax except its stickiness. A little is mined in Utah and about 3 000 tons are imported annually from Galicia and Moldavia. Used in crude state as insulation for electric wires. By distilling it yields ceresine, used for candles, burning oils, paraffine, a product like vaseline and a residuum which, with india-rubbur, constitutes the insulating material called okonite. Patronite (vanadium sulphide). At the one locality of Cerro de Pasco, Peru, there is a vein 7 or 8 ft thick of a nearly black material resembling slaty coaL About two-thirds of this is patronite and one-third metallic sulphides and free sulphur. Below it is 1 to 2 ft of coke-like material, chiefly carbon, which blends into a lustrous black material 4 to 6 ft thick, containing more sulphur carbon, but known as asphaltite. The ashes of these two associates are also rich in vanadium, H the roasted or burned material is exported. Petroleum is a mixture of hydrocarbons, obtained from the earth. It varies from a light, easily flowing liquid, to a thick viscous oil, and is usually of a dark brown or greenish color, with a distinct fluorescence. Chemically the American petroleum consists principally of hydrocarbons of tha paraffine ssries CnH2n+2, with smaller amounts of the series CnHjn and CnHjn-ts. The oils from Baku, on the Caspian, Rangoon, Galicia, and the Caucasus, contain more of the C„H 2n or olefin series. Roscoelite (vanadium mica). A mica of brown to brownish-green color, long known as an associate of gold in certain mines of California, and containing approximately 25% V2OJ, is now commercially obtained from a soft Colorado sandstone of greenish color, in which the roscoelita fills the interstices between the grains. Thorianite (ThOaUsOg). Small water-worn blackish cubic crystals found in the Ceylon gem gravels and used as a source of thoria. H = 5.5 to 6, G =» 9.3. It is radioactive. Thorite (ThSiOi). Black or orange-yellow, zircon-likeicrystals and masses, occurring in Nor way in small quantity; used as a source of thoria. H 4.5 to 5, G = 4.8 to 5.2. Infusible; gelatinizes with acids. Tripoli. A fine, siliceous powder, containing chalceddhy or opal; used as abrasive; day-like in appearance, but quite gritty. Umber is drab-colored mixture of iron and aluminum silicates, containing manganese oxide. It becomes reddish brown on burning. Sienna is similar, but with less manganese and lighter in color. Vermiculite. Various forms of soft, pliable or inelastic mica; when heated, slowly expanded material useful in heat insulation. Wad. Earthy to compact indefinite mixtures of oxides, especially of manganese, cobalt or copper, are known as wad. They have no constant characters, but may be valuable ores. Usually dark brown to black in color.
INDEX TO DETERMINATIVE TABLES* (Numbers indicate the sections in the tables) Actinolite (see Amphibole) Albite (see Plagioclase) Aluminite, 23 Alunite, 18 Alunogen, 7 Amber, 25 Amblygonite, 19 Amphibole, 20, 21 Analoime, 20 Andalusite, 23 Anglesite, 16 Anhydrite, 18 Anorthite (see Plagioclase) Antimony, 4 Apatite, 22 Apophyllite, 19 Aragonite, 24 Argentite, 1 Arsenic,4 Arsenopyrite, 3 Asbestos (see Amphibole) Asphalt, 25
BIBLIOGRAPHY Descriptive Mineralogy. .Treatises Dana, J. D. System of Mineralogy, 6th ed,' with three appendices. John Wiley & Sons, N Y, 1892 Hintze, Carl. Handbuch der Mineralogie. Bd 1, 1897; Bd 2,1904. von Veit & Co, Leipzig Descriptive and Determinative Mineralogy. Text Books and Treatises Cahern and Wooton. The Mineralogy oi the Rarer Metals. 2nd ed. Charles Griffin & Co, Ltd, London, 1920 Dana-Fora. Textbook of Mineralogy. 4th ed. John Wiley & Sons, N Y, 1932 Kraus, E. H., Hunt, W. F. and Ramsdell, L. S. Mineralogy. Introduction to the study of minerals and crystals. McGraw-Hill Book Co, N Y, 3rd ed, 1936 Miers, H. A. Mineralogy. An Introduction to the Scientific Study of Minerals. Macmillan & Co, London, 1902 Rogers, A. F. Introduction to the Study of Minerals. 3rd ed. McGraw-Hill Book Co, N Y, 1937 Brush-Penfield. Manual of Determinative Mineralogy. 16th ed. John Wiley & Sons, N Y, 1906 Fraser-Brown. Tables for the Determination of Minerals. 6th ed. J. B. Lippincott Co, Philadelphia, 1910 Kraus-Hunt. Tables for the Determination of Minerals. 2nd ed. McGraw-Hill Book Co, N Y, 1930 Lewis, J. V. Determinative Mineralogy. 14th ed. Revised by A. C. Hawkins. John Wiley & Sons, N Y, 1931 Plattner-Koibeck. Probierkunst mit der Lötrohre. 7th ed. Johann Barth, Leipzig, 1907 Warren, C. H. Determinative Mineralogy. MeGraw-Hill Book Co, N Y, 1921 Crystallography Bayley, W. S. Elementary Crystallography. McGraw-Hill Book Co, N Y, 1910 Groth-Jackson. The Optical Properties of Crystals. Translated from 4th ed. John Wiley & Sons, N Y, 1910 Groth-Marahali. Introduction to Chemical Crystallography. John Wiley & Sons, N Y, 1906 Lewis, W. J. A Treatise on Crystallography. Univ Press, Cambridge, England, 1899 Tutton, A. E. H. Crystallography and Practical Crystal Measurement. 2 vols. Macmillan & Co, London, 1922 | Minerals in Thin Section ^ Iddings, J. P. Rook Minerals. 2nd ed. John Wiley & Sons, N Y, 1912 Johannsen, A. Essentials for the Microscopic Determination of Rock Forming Minerals and Rooks. Univ of Chicago Press, 1922 Johannsen, A. Manual of Petrographie Methods. McGraw-Hill Book Co, N Y, 1914 Pirsson, L. V. Rocks and Rock Minerals. John Wiley & Sons, N Y, 1908 Rogers, A. F., and Kerr, P. F. Thin Section Mineralogy. McGraw-Hill Book Co, N Y, 1933 Wemschenck-CIark. Petrographie Methods. McGraw-Hill Book Co, N Y, 1912 Microscopic Study of Mineral Fragments Larsen, E. S., and Berman, H. Mioroscopic ¡Determination of the Non-opaque Minerals. U S G 8 , Bull 848, 1934 Schroeder van de Kolk, J. L. C. Tabellen zur mikroskopischen Bestimmung der Mineralien nach ihren Brechnungs-exponenten. 2nd ed. Wiesbaden, 1906 Winchell, A. N. Elements of Optical Mineralogy. Part L 5th ed. John Wiley & Sons, N Y, 1937 Microscopic Study of Opaque Ore~mineral8 Davy-Famham. Microscopic Examination of Ore Minerals. McGraw-Hill Book Co, N Y, 1920 Murdoch, J. Microscopic'Determination of Opaque Minerals. John Wiley & Sons, N Y, 1916 Schneiderhöhn, H. and Ramdohr, P. Lehrbuch der Erzmikroskopie. Berlin, 1934 Short, M. N. Microscopic Determination of Ore Minerals. U S G S Bull 825, 1931 Van der Veen, R. W. Mineragraphy and Ore-deposition. G. NaeS, The Hague, 1925 Occurrence, Association and Origin of Minerals Byschlag-Krusch-Vogt. Die Lagerstätten der nutsbaren Mineralien und Gesteine. Enke, Stuttgart, 1909 Clarke, F. W. l i e Data of Geochemistry. Bulletin 770, U S G S, 1924 Merrill, G. P. The Non-metallio Minerals. 2nd ed. John Wiley & Sons, N Y Van Hise, C. R. A Treatise on Metamorphism. Monograph 47, U S G S, 1904
Ferdinand
Uses of Minerals Ladoo, R. B. Non-metallic Minerals. McGraw-Hill Book Co, N Y, 1925 Mineral Resources of the United States. Annually since 1883, U S G S; from 1932, Bur Mines The Mineral Industry. Annually since 1892, McGraw-Hill Book Co, N Y Spurr-Wormser. Marketing of Metals and Minerals. McGraw-Hill Book Co, 1925 Mineral Raw Materials. U S Bur Mines Staff, 1937 Qems and JPrecious Stones Bauer, Max. Precious Stones. Trans by L. J. Spencer. 1904 _ Bauer, Max. Edelsteinkunde. Revised by Schlossmaoher. Leipzig, 1932 Cattelle, W. R. Precious Stones. J. B. Lippincott Co, Philadelphia, 1903 Eppler, A. Die Schmuck- und Edelsteine. Felix Krais, Stuttgart, 1912 Kraus-Holaen. Gems and Gem Minerals. 2nd ed McGraw-Hill Book Co, N Y , 1931 Smith, G. F. H. Gem Stones. Methuen & Co, Ltd, London
SECTION 2 GEOLOGY AND MINERAL DEPOSITS BY
JA M E S F U R M A N K E M P L A T E PB O F E SS O B O F G E O LO G Y , CO LU M BIA TJNTVEB8ITY B E V I BED B Y
PAU L F. K E R R PB O F E SS O B O F M IN E B A L O G Y , C O LU M BIA U N IV E R S IT Y
GEOLOGY PAGE 1. Introduction.......................................... 02 2. Chemical Composition of Rock-forming Minerals............................................. 02 3. Rock-forming Minerals......................... 02 4. Igneous Rooks....................................... 03 5. Sedimentary Rooks............................... 07 8. Metamorphic Rooks............................. 09 7. Forme Assumed by Igneous Rocks___ 09 8 . Forms Assumed by Sedimentary and Metamorphic Rocks........ . ............... 11 9. Rock Disturbances............................... IX 13 l 6. Faults..................................................... 11. Joints, Unconformities, Outcrops and Erosion............................................... 15 12. Summary of Stratigraphic Geology.. . 17 AST.
MINERAL DEPOSITS: ORES 13. Introduction. Definitions of Ore.. . . 14. Metals in the Earth’s Crust.................
18 18
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15. Calvities in Rooks; Ground-waters.. . . 18 16. Mimerais and Localization of Ore.............................................19 17. Classification of Ore-deposits ...20 ...20 18. Iron.................................... 19. Copper............... ...22 20. Lead and Zinc................ ...23 21. Silver and Gold ...24 22 . Minor Metals ...26 MINERAL DEPOSITS: WON-METALLIC MINERALS 23. Abrasives. Asbestos. Asphalt ... 28 24. Building Stone, Clay, Cements, Limes 28 25. Carbon Minerals: Coals, Petroleum, etc......... ................................................ 29 26. Miscellaneous Non-metallio Minerals.... 32 Bibliography...................... ... 33
17ote.— N u m b e r s i n p a ren th eses i n t e x t r e fe r t o B ib lio g r a p h y a t e n d o f th is seotien .
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IG N E O U S R O C K S
GEOLOGY 1. INTRODUCTION A rock is a mineral or aggregate o f minerals, forming an essential part of the earth; but many important mineral bodies, such as ores o f metals, are not to be considered as rocks. Of about 1 500 species of minerals, only 20 or 30 are important as rock constituents. The three great classes of rocks are: I g n e o u s , solidified from fusion; S e d i m e n t a r y , deposited in water or air; M e t a m o r p h i c , recrystallized or otherwise altered igneous and sedimentary rocks, such that their original character has been obscured. Igneous rocks are believed to have been the predecessors and source o f all others (1, 2, 3). An analysis, illustrating g b o s s c o m p o s i t i o n of the outer 10 miles of the earth, is given in Sec I, Art 1. Compared with the percentages there stated, niekel and iron probably become increasingly abundant toward the earth’s center. Most abundant elements of rook-forming minerals are: silicon, oxygen, aluminum, iron, mag nesium, calcium, sodium, potassium, and hydrogen; secondarily, carbon, chlorine, phosphorus, titanium, manganese, and sulphur. All other elements, even the familiar copper, lead and sino, and the precious metals, or an abundant atmospheric gas, as nitrogen, are small in amount.
2,
CHEMICAL COMPOSITION OF ROCK-FORMING MINERALS
Rock-forming minerals comprise silicates, oxides, carbonates, sulphates, chlorides, phosphates, sulphides, and native elements. Silicates are the most important, whence silicic acid, in various forms, is the foremost acid in Nature. Three principal forms of silicic acid are represented in the rock-makinjg minerals: HiSiOs (metasilicic), H 4S1O 4 (orthosilicic), and HiSijOg. Pyroxenes, amphiboles, and leucite are salts o f metasilicic acid. Micas, olivine, anorthite, nephelite, garnet, and many minor minerals are orthosilicates. Orthoclase and albite are salts of HiSiaOa. Some silicates have only the usual bases, aluminum, iron, magnesium, calcium, and the alkalies, and are called a n h y b b o u s ; others, usually formed b y weathering or alteration o f the first, contain hydrogen and oxygen in such proportions as to be driven off as water, and are called h y d r a t e d s i l i c a t e s . This distinction is rendered important b y the gen eral secondary character of hydrated silicates. The chief anhydrous silicates in igneous rocks embrace the following mineral groups: feldspars and feldspathoids, pyroxenes, amphiboles, micas, and olivine. Rarer and less important are: zircon, sphene, tourmaline, and analeime. On weathering or other alteration, the hydrated silicates, kaoiimte, chlorite, and serpentine, usually result. Metamorphic rocks contain a few characteristic silicates, besides the common ones o f igneous rocks, v iz: staurolite, sillimanite, kyamte, andalusite, scapolite, and epidote. Oxides are next important, o f which quartz (SiOz) stands first, being abundant in the great classes o f rocks. The related forms o f silica, chalcedony, cristobalite and tridymite, pnd the hydrated variety, opal, should also be noted. Next are the oxides o f iron, magnetite and hematite, and the hydrated form, Jimonite. W ith magnetite are associated chromite and ilmenite (FeO -TiO i), Water, whether liquid or ice, is technically a mineral. Carbonates are calcite, dolomite, and siderite, with their intermediate mixtures. They are of chief importance in sedimentary and metamorphic rocks, occurring rarely in igneous rocks, except as products of weathering. There are two common s u l p h a t e s , anhydrite and gypsum. One c h l o r i d e , common salt, alone merits attention. The p h o s p h a t e s are apatite and collophane. Tw o s u l p h i d e s , pyrite and pyrrhotite, are widely distributed. The one n a t i v e rock-forming element is graphite.
3. ROCK-FORMING MINERALS (1, 2, 3) Minerals o f t h e i g n e o u s r o c k s are grouped according to their usual order o f c r y B t a lliz a - * tion into: 1. Iron ores and minute associates. 2. Ferromagnesian silicates (olivine, pyroxenes, amphiboles, and micas). 3. Feldspars and feldspathoids (piagioclase, ortho clase, nephelite, leucite, and analeime). 4. Quartz, in acidic a n d higher m e d i u m rocks only. For descriptions, see Sec I, Determinative Tables.
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2-03
Minerals of the sedimentary rocks are ordinarily fragments of minerals from igneous rocks. Quartz is most resistant to solution, alteration, and abrasion, and therefore appears in almost all aanda and sandstones. The others are less frequent. After quartz, carbon ates are of chief interest. Calcite and dolomite constitute the limestones, sometimes with slight admixture of siderite. Kaolin!te, montmorillonite and hydromica enter the fine sediments. T he tw o sulphates, gypsum, the more abundant, and anhydrite, appear only in sedimentary rocks. T he same is true of the chloride, rock salt. Minerals of the metamorphic rocks. The components, of both sedimentary and igneous rocks, when deeply buried, with attendant heat and pressure, recrystallize. at times to distinctively metamorphic minerals. Silica, being omnipresent, survives as quartz. The aluminous components afford andalusite, sillimanite, and kyanite. Magnesias, iron, and aluminous compounds yield abundant biotite and occasional epidote. Lime, in asso ciation with ferric iron or alumina, makes garnet possible, but orthoclase may become muscovite. The feldspars are important components. The ferromagnesian minerals (chlorite and serpentine) are derived from magnesium- and iron-bearing originals.
Summary of Rock-forming Minerals Igneous Rocks.
Q uabtz F e l d s p a b s : o r t h o c la s e , p ia g io c la s e F e l d s p a t h o id b : n e p h e lin e , le u c it e , a n a le im e , m e lilite P y e o x b n e b : h y p e r s th e n e , d io p s id e , a u g ite , s o d a -p y r o x e n e s A m p h ib o l e s : h o r n b le n d e , s o d a -a m p h ib o ie s M i c a s : b io t it e , m u s c o v it e O t h e b M in e b a l s :
o liv in e , m a g n e t it e , ilm e n it e , a p a tite , z ir c o n
4. IGNEOUS SHOCKS Structures and textures. In a broad way, igneous rocks, as contrasted with sedimen tary and metamorphic, have a massive structure; that is, their minerals are not arranged in parallel or distinct layers. Massive is in many respects a synonym of igneous. Exam ined more in detail, as in hand-specimens, they have 4 common textures. Where the molten mass has been too quickly chilled to crystallize, the texture is g l a s s y . This texture appears on outer borders o f thin masses, on upper surfaces o f lava flows, and, in relatively infusible varieties, it may extend through an entire flow. I t is most frequent in siliceous rocks, which have high fusing points; it is rare in the medium, and scarcely known in the bade. Where molten masses have cooled rather rapidly, and yet n ot so quickly as to prevent crystallization, very fine-grained textures result, called f e l s i t i c . But, if older, larger, and already well-formed crystals at the time be swimming in the magma, which then crystallizes in relatively small components, the texture is called p o b p h y k e t i c . The Urge crystals are called p h e n o c r y s t s and the matrix the g b o u m p - m a s s . Phenocrysts of acidic rocks are chiefly quartz and feldspars; the dark ferromagnesian silicates are much less common. In medium rocks, quartz practically fails, and feldspars are associated with more of the ferromagnesian minerals. In basic porphyritic rocks, feldspars decline, while augite and olivine, and very rarely biotite and hornblende, gradually replace them. When a molten magma crystallizes into an aggregate o f fairly coarse components o f about the same size, the texture is g r a n i t o i d (like granite). Rarely, in these coarsely crystalline rocks, the feldspars become unusually large and stand out in contrast with the rest. As a result of explosive outbreaks at volcanic vents, igneous rocks are sometimes blown out as fragments of all sizes, from impalpable dust to large bombs. The fragments settle down on the sides of the cone or at greater distances, and yield rocks with marked fragmental texture, allied to sedi ments. If coarse, they are called b b e c c i a s ; if fine, t u t f b . Chemical composition of igneous rocks. S i l i c a ranges from about 80% to a theoretical minimum of 0 % in certain igneous iron ores; only in rare cases does it fall below 40% . Igneous rocks containing above 65% silica are called a c i d i c ; those with 55 to 65%, m e d i u m ; below 50% , b a s i c . Of a l u m i n a the superior lim it is 25 to 3 0 % ; general range, 12 to 1 8 % ; minimum, nearly 0 . I b o n o x i d e s are low, 1 % or less, in the most acidic rocks, but increase in the basic to 10 to 2 0 % ; in rare extremes, 90 to 95% . M a g n e s i a sinks to a mere trace in the acidic, rising with fail o f silica to 30% in the extremely basic. L i m e is low in the acidic, gradually increasing to about 15% maximum in certain basic rocks, P o t a s h is highest in the rare leucite rocks, reaching 10 or 12% ; it ranges from
Hooks of this series are: t b a c h t t e , felsitic texture, few phenocryais; t b a c h t t e - p o b p h ^ t (syns, porphyry, orthoclase-porphyry), felsitic ground-mass, abundant phenocrysts; s t b k i t e p o h p h y b t . predominant phenocrysts, subordinate ground-mass; s y e n i t e , granitoid texture, some* times varied by abnormally large feldspars. Syenitic-pegmatities are known, but are leas frequent than granitic,
M 0 1
Syenite
Trachyte-syenite series embraces igneous magmas containing: silica, 55 to 65% ; flfonmift, 15 to 2 0 % ; iron oxides, 1 to 3 % ; magnesia, 1 to 2 % ; lime, 1 to 3 % ; potash and soda, 7 to 12% . Th ey are much less common than the rhyolite-granite series. On crystallizing they yield finely to coarsely crystalline rocks, consisting of orthoclase, acidic plagioclase, and usually notable proportions o f the dark silicates, biotite, hornblende, and augite, one or several. Quartz fails, or, at most, is extremely subordinate. Light-colored minerals are in excess.