A treatise on metalliferous minerals and mining

Front matter

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Preface

TO

THE SECOND EDITION.

The necessity for a second edition of this book has enabled me to make several corrections and additions which will help towards its exactitude and completeness. I am pleased that these do not affect the truth of the general principles and inferences laid down or deduced in the book. Time will show, I think, that these principles and inferences are founded upon a true reading of world-wide geological phenomena, and are consequently in harmony with actual mining experience.

For the most part the book has been very favourably received by the press, and my reviewers will see that I have to some extent availed myself of their various suggestions and, in most cases, fail criticism.

The design of the book is stated in the Pre&ce to the first edition, and it does not aim at anything beyond that purpose.

VI PREFACE.

It simply seeks to set forth, for ordinary English readers, the

substance of our knowledge on Metalliferous Minerals and

Mining.

If it fulfils this purpose, it will achieve what I desire for it — a permanently usefid place in English mining literature.

D. C. Davies.

Ebnal Lodge, Gobowen, Oswestry : September i88o

PREFACE

TO

THE FIRST EDITION.

This book is designed to describe, in a concise and systematic manner, the conditions under which metals and metallic ores are found in the diflferent countries of the world.

It is hoped that such a description will serve, first, to explain to some extent the origin of deposits of metalliferous minerals ; and, secondly, by defining the zones occupied by the various metallic ores, to lessen somewhat the amount of unsuccessful search for them.

My hope is that by the data given, together with the figures, quantities, and results contained in the book, the commercial conditions of mining success may be better defined.

The books referred to in the following pages show that there is no lack of mining literature, much of which is of a high order. Still, other persons may have felt, with myself, the want of a book covering the ground and fulfilling the purpose and plan of this volume. My endeavour in writing it has been to illustrate great principles by a sufficiency of representative details, and to refer the reader to sources where additional vili PREFACE.

illustration, as well as the enumeration of the minuter details of mining, may be found.

The explanations of scientific and of mining terms which are appended will, I hope, facilitate to ordinary readers the comprehension of the whole of the matters treated qt

The illustrations have been prepared by my son, Mr. E. Henry Davies, and my thanks are due to him for his willing and efficient co-operation.

My sincere wish is that this book may prove of real service to all those who are engaged in a profession which is as honourable when honestly followed as it is arduous and difficult in practice.

D. C. Davies.

Chapter I. Materials Of Which The Eakth Is Made

PAGE

List of Simple Elements — How Distinguished and Characterised — Metalliferous Minerals selected for description in this book — Table of Strata — General Geological Position of Metallic Minerals — Great Parallel Mountain Chains of the World ....

Chapter II. Classification Of The Deposits Of Metalliferous Minerals

Lodes— Description and Origin — Lodes of Displacement — Gash Veins — Horses — Caunter Lodes — Displacement of Lodes — Dykes — Elvan Courses — Considerations affecting the Dip of Lodes — Earthy Minerals of Lodes — Gossan, Peachy, Caple, Pryan, Quaxtz, Sparry, Flucan, and Grouan Lodes 8

CHAPTER HI.

METALUC CONTENTS OF LODES.

Affected by Nature of Strata — Modes of .Occurrence — Origin and Derivation — Infiltration — Condensation — Sublimation — Causes affecting the Particular and Local Deposition of • • • • I7

CONTENTS.

Chapter IV. Second, Third, And Fourth Classes Of Mineral Deposits

PACK

Stratified Mineral Deposits— Irregularly Stratified Deposits — Contact Deposits — Segregated and Crystalline Masses of Ore — Flats — Irregular Deposits — Pockets — Contact Deposits — Network of Veins — Disseminated Ores— Superficial Deposits . . '25

Chapter V. Gold

Characteristics and Modes of Occurrence — Drifts 1 Gold— Nuggets — Gold in Lodes and. Veins — Alluvial Deposits of the Ural Mountains — Mining in the Solid Rock — Austro- Hungary — Mines of the Banat — Gold in Central Europe — Sands of the Rhine — Lodes and Alluvium of France, Spain and Portugal, and Italy . . • 32

CHAPTER VL

GOLD— continued.

Gold Deposits of Gogofau — The Dolgelly District — Scotland — Ireland— /» situ and in Alluvial Deposits in County Wicklow . 40

CHAPTER X. GOLD-^continufd

New 2^a]and — History— Gold in «^— Gold in Drifts— Africa— Gold Fields of Leydenberg — India — Philippine Islands— Aruba Island — Concluding Remarks . .75

CHAPTER XL

(general Characteristics — Its Ores — Silver in Russia, Austria, Bohemia, and Saxony — Description of the Mines of the Erzgebirge^ — Hanover and Brunswick — Nassau — France, Spain, Norway, and Great Britain 81

CHAPTER XV. COPPER—conUmucL

Tlie Ores of Copper in Russia — Ural Mountains — Western Side of the Ural Mountains— Caucasus — South Africa— The Cape— Algieis — Spain — Italy — Austria — Germany : Prussia — Norway — Sweden and France I18

CHAPTER XVI. COPPER^corUinuetL

British Isles — Cornwall — Geological Structure and Characteristics of the Mining Districts of the County— Special Features of Lodes— Dolcoath Mine — History of Copper Mining in the West of England 1 25

CHAPTER XVII. COPPER— conHnued

Cupreous Sandstones of Cheshire and Salop — The Limestones of Salop and North Wales— The Parys Mines of Anglesea— The Copper Turf of Merioneth — Copper in Carnarvonshire and Cardiganshire — North- West of England, and County Wicklow in Ireland 136

CHAPTER XVIIL COPPER— C9ntinuid,

Copper Deposits of North-Eastem America — Nova Spotia to Carolina — Mississippi Valley, Wisconsin— Lake Superior — Canada . .148

CHAPTER XIX. COPPER— cotUinual

Western North America — Colorado, Montana, Nevada, and Arizona — Wyoming — Cuba— Jamaica — South America— Venezuela and Chili — Australasia — North and South Australia — York Peninsula — Flinders Range — Victoria — New South Wales— Japan— Inferences and Concluding Remarks 156

CONTENTS. Xlll

Chapter XX. Tin

PACK

General Description — Modes of Occurrence — Alluvial Mining in Banca — In the Malay Peninsula - Tin Ore Deposits of Bohemia and Saxony^France and Sweden 164

CHAPTER XXI. TIN-conHnued

Tin in the British Isles— Cornwall — Imp>ortance and Antiquity of the Industry— Brief History of Tin Mining in the Coun|y— The Great Flat Lode— Cligga Point— Remarks on the Depths of Mines, and on the Particular Structure of the Tin Lodes of Cornwall , * 17 1

CHAPTER XXII. TIN-^ontimud

Alluvial Tin Deposits of Cornwall — Tin in Bolivia, Queensland, New South Wales, Victoria, and Tasmania — General Deductions and Concluding Observations 182

Chapter XXIII. Lead

Native— Ores of Lead — Lead Ores of Austro-Hungary— Banat— Carinthian Alps— Bleiberg— Germany — Erzgebirge— Hartz— Clausthal and Teller- Nassau — Rhenish Provinces— Spain — Brief History — Andalusia — Siem^ de Almagrera — Linares — Homachos — France — Pontgibaud — Poullaouen — Bretagne — Belgium . .189

CHAPTER XXIV. LEA D — continued

Lead Mines of the British Isles— Statistics— Lead Mines of Shropshire, — Montgomeryshire— The Van— Cardiganshire — Brief History of the Lead Mines of Cardiganshire, and Modes of Occurrence of the Ores , 200

XIV CONTENTS.

CHAPTER XXV. LEAD— continued

PACK

Lead Mines of Carnarvonshire, of the Isle of Man, of Cornwall — West Chiverton, of Devon, of the North of England — Northumberland, Durham, Westmoreland, and Cumberland, of Yorkshire, of Derb)rshire — Lead Mines of the Limestones of Flintshire and Denbighshire — Lead Mines of Ireland 213

CHAPTER XXVL

LEAD— continued.

Lead Mines of North-Eastem America — Canada — New England States — Wisconsin, Illinois, and Iowa — Carbonate of Lead in Colorado — Summary and Deductions 233

CHAPTER XXVIL

ZINC,

General Remarks — Ores of Zinc — Zinc Ores of Siberia, Hungary, Silesia, Sardinia, Algeria, Belgium, Great Briuin and Ireland, America, Eastern America— New Jersey— Zinc Ores of the Lead Region of Wisconsin, of the Western States— Concluding Remarks 241

CHAPTER XXVIIL IRON,

Wide Distribution— Native Iron— Ores of Iron— Stratigraphical Groups of Iron Ores— Iron Ore Deposits of India— Austria — Germany—Nassau—Other German States— Sweden and Norway — Belgium— France— Spain— Algeria 250

CHAPTER XXIX.

IRON— continued.

Iron Ore Deposits of the British Isles — Cornwall — Devon — Forest of Dean — Lancashire and Cumberland— Iron Ores of the Coal-measures— Divisions of the Coal-measures, and Iron Ores of each Division— Iron Ores of the Liassic and Oolitic Strata— Of Yorkshire, Lincolnshire, and Northamptonshire — North-East of Ireland 262

CONTENTS. XV

CHAPTER XXX IRON—coniimud.

PACK

Ores of the Dominion of Canada — Nova Scotia — ^The United States — Eastern States— Missouri — Michigan and Lake Superior—Of Australasia— General Deductions • 275

CHAPTER XXXI.

VARIOUS METALS,

Mercury Ores and Distribution — Bismuth— Nickel— Platinum— Iridium — Palladium and Tellurium 281

CHAPTER XXXII.

ON^ THE DISCOVERY AND PROVING OF MINES,

Old Superstitions — The Strata containing Metalliferous Minerals — The Stratigraphical Zones of the different Minerals — Discovery of Mines apparently accidental not really so — Surface Indications — Shoding— Explorers — Prospecting — Contents and Character of Lodes — Proving by Trenches, Small Shafts, Adits, Shafts and ' Levels along Lode, Sumps , 292

CHAPTER XXXIII.

ON THE WORKING OF METALLIFEROUS MINES,

Shafts— Vertical — Diagonal — ^Arrangement — Winding Compartment — Pumping Compartment — Ladders — Man-Engines — Cages, Guides — Adit Levels — ^Working Levels — Winzes — Stopes — ^Timbering — Ironstone Mining in Coal-measures— In Jurassic Strata . 303

CHAPTER XXXIV.

ON THE WORKING OF METALLIFEROUS MINES-- continued.

Timber — ^Ventilation — Temperature, Fans— Old Methods of Breaking Rocks down — Drilling — Single Hand — Double Hand — Underhand — Rock Drilling Machines — History — Classesof Drills— Principles of Construction — Detailed Construction — Air Compressors — Receivers, Pipes — Hand Boring Machines — Jordan's — ^Victor's — a

XVI CONTENTS.

CHAPTER XXXV.

ON THE WORKING OF METALLIFEROUS MINES^ continued.

Explosives — Gunpowder —Compositions of Various Kinds— Principle of Explosion from Nitro-Glycerine— Dynamite— Lithofracteur — Tonitc — Gun-cotton — Patent Gunpowder — Explosion by Detonators — Saving that could be Effected often Prevented by Miners — Plan adopted in American Mines — Danger — Firing by means of Electricity 331

CHAPTER XXXVI.

ON THE WORKING OF METALLIFEROUS MINES-- continued.

Drainage and Pumping — Ancient Methods — Barrels— Hand Whims — Horse Whims — Water Wheels — Newcomen's Engine — Watt's Engine — Saving effected in Fuel — Register of Duty, 1812, 1S44, 1878 — Tables of Work done — Improvements resulting in Increase of Duty, in Boilers, Engines, Shaft Appliances — General Descrip- ' tion of Pumping Arrangements in a Shaft — Other Pumps — Hydraulic- power— Windmills— Great Tunnels for Drainage— Blackett, Halkyn, Redruth, Kit Hill, Ernst August, Rothshonbergen, Emperor Joseph, Comstock 339

CHAPTER XXXVII.

ON THE DRESSING OF METALLIC ORES,

Picking and Sorting— Crushing with Hammers— Spalling— Orebreaking Machines -Blake's and others — Stamping and Stamps — Old Cornish Stamps — Improved Stamps— Work done by them — Work done by American and Australian Stamps— Recently Invented Stamps — Patterson's Elephant Ore Stamp — Shell's Pneumatic Stamp— Husbaud's Stamp — Harris's Annular Stamp Head— Cox's Stamping Machine 350

CHAPTER XXXVIII.

ON THE DRESSING OF METALLIC ORES^continued,

Jigging— The Different Specific Gravity of Different Mineral Substances — A Reason why they can be Mechanically Separated — Table of Ratas at which various substances fall through Water-

CONTENTS. xvil

PAGK

Introduction of Hand Jigging— Mechanical Jigging — Principle of Jigging— Jigs with Movable Sieves— Jigs with Fixed Sieves— Self-acting Continuous Ore Dressing Machinery ~ Green's — Rotating Jig or Buddie— Buddies — Ordinary Round Buddies — Slime Pits— Tozing — Machinery for Retreatment of Ores — Dressing Tin, Copper, Silver, Gold — Methods pursued in Brazil and in Victoria . 363

CHAPTER XXXIX.

HYDRAULIC GOLD MINING,

The Pan— Cradle— Long Tom— Broad Tom— Artificial Sluice- Natural Sluice— Top Unproductive Drift — Mining— Hydraulic Excavation— Runs— Cleaning up, &c 575

CHAPTER XL.

SUNDRY PARTICULARS OF WORK AND COSTS,

Gold — Quartz Mining— Alluvial and Hydraulic Mining — Tables of Particulars. — Silver — Altai Mountains — Dry Ore Concentration — Mode of Treatment in Mexico — Copper — Cape Mines — Algerian Mines— Parys Mountain Mine^ — Lake Superior Copper Mines — Tin— Costs of Work in Cornwall — Percentage of Black Tin to Ore— Of Black to Metallic Tin— Cost of Dressing— Cost of Prepared Ore per Ton— Banca, Australia, Red River, Cornwall, Stream Tin Workings— Lead — Various Costs— Zinc — Various Costs— Iron —Various Costs —Deepest Mine Shafts in the World . 382

CHAPTER XLI.

GENERAL CONSIDERATIONS.

Large Proportion of Unprofitable Mines — Unsuccessful British Mining in America — Causes — Want of Knowledge of First Principles — Insufficient Capital— Excess of Unproductive Capital — Exorbitant Prices Paid for Mines — Expensive General Management — Ditto Local Management — Mine Gambling — Rules to Regulate the Sale and Purchase of Mines— Possible Reduction in the Cost of Working Mines— Remedies — Possible Future of Successful Mining — Concluding Observations 397

Glossary of Words and Terms used in Mining, and of Scientific

Words used in this Book 405 ,

Index 433

LIST OF ILLUSTRATIONS.

FIG. PAGB

1. Lodes in the Strata of Flintshire, North Wales .... 9

2. Illustration of the various relative positions of lode and strata . . 10

3. Illustration of lode on a line of displacement of strata . . 10

4. Section of lode at the Neugluck Mine, Freiberg, showing * horses *

in lode ii

5. Illustration of 'caunter' or contra lodes 12

6. Section of Old Wheal Agnes Tin Mine, Cornwall, showing dis-

placement of lodes by faults 13

7. Illustration of horizontal displacement of lode . . . •IS

8. Section of lode at Christbescherung Mine, near Freiberg, showing

rounded masses of rock and ore . . . . * . 18

9. Section of a sparry lode near Freiberg 19

10. Section of the Drei Prinzen Lode, Freiberg 20

11. Section of lode at Alte Hoffnung Gottes Mine, near Freiberg . 21

12. Section of another lode at the same mine, showing ore and vein

stuflfin layers 22

13. Illustration of a crack following line of weakest resistance . . 27

14. Section of lode at Alston Moor, showing changes of dip and pro-

ductiveness of lode 28

15. Section showing the two conditions under which gold is usually

found . • • 35

16. Section of gold diggings, south of Miask, in the Ural Mountains 37

1 7. Section through the Oravicsa group of mines. South- West Hungary 37

18. Ideal section across the Appalachian chain of mountains . . 45

19. Section of gold strata at Woodville, Virginia 46

20. General section, from the Sierra Nevada into California . . 52

21. Section of gold strata near Congo Soco, Brazil . . . . 58

22. Section of the Bahu portion of gold lode at St. John del Rey

Mine, Brazil 60

23. Section of strata through the gold districts of Victoria . . . 65

24. Auriferous gold reef near Ballarat, with method of working ■« 66

LIST OF ILLUSTRATIONS. xix

FIG. PACK

25. Section of the New South Wales Carbonifeious strata . . 67

26. Illustratioii of gold drift at the base of the Coal-measures, New

South Wales 68

27. Illustration of the intimate structure of a gold quartz reef in New

South Wales ... 69

28. Another illustration of the same 69

29. \

I Sections of the older gold drifts of Victoria, with superincumbent

* j drifts and basalts 7i» 72

32. Horizontal section of the older gold drift of Victoria, showing

position of leads 72

33. Section of newer gold drift on Macquarie River, New South

Wales 73

34. Section across the Province of Otago, New Zealand . . . 75

35. Section through the Leydenberg Gold Field, South Africa . . 77

36. Cross section at Simon Judas Mine, Banat, South-East Hungary 84

37. Diagram section across the Erzgebirge Mountains . . .86

38. Diagram of the Silver Fahlbands, Konisberg, Norway . . » 91

39. Section across the Comstock lode and its enclosing strata . . 96 4a Longitudinal section of the Comstock lode, showing the mine

workings upon it . . 97

41. Illustration of the structure of Ruby Hill, Nevada . . . 100

42. Transverse section of the Great Ore Chamber, Emma Mine . . 104

43. Ai^entiferous strata, Santa Rosa Mine, Peru .... 108

44. Section of strata and description of the principal lode at Chanara-

dllo, near Copiapo, Chili 1 1 1

45. Section of pyrites deposit, Buitron Mine, Huelva, Spain . .120

46. Diagram showing the mode of occurrence of copper ore, Fahlun,

Sweden 123

47. Section of strata from Boscastle to Pencarrow Point, Cornwall . 126

49. l Detailed sections of copper lodes, Cornwall 132

51. Old section of workings on the Gaunter lode, Dolcoath Mine,

Cornwall 133

52. Section of copper shale bed in limestone, Shropshire . . . 137

53. Section across strata and copper deposits at the Parys Mine,

Anglesea 140

54. Section of workings on the Great Open Cast, Parys Mine,

Anglesea 141

55. Section of workings on the North Discovery lode, Parys Mine,

Anglesea , . . . . 142

XX LIST OF ILLUSTRATIONS.

PIG. PACK

55A. Illustration of the copper and pyrites deposits, Old Balljrmur-

tagh Mine, Ireland 146

56. Section of lode at Tigroney Mines, Ovoca, Wicklow, Ireland . 146

57. Section of the cupriferous bed at the Dolly Hide Mine, Mary-

58. Section of strata in the Lake Superior Copper Region . .150

59. Section at Waterbury Copper Mine, Lake Superior . . . 151

60. Section at Eureka Mine, Lake Superior 1 52

61. Section of workings at the Cliff Mine, Lake Superior . . . 153

62. Section* of strata in the Ontonagon Copper District, Lake

Superior 154

63. Section of copper deposits, near Copiapo, Chili . . . . 158

64. Section of the alluvial tin deposits, Banca . . . .165

65. Section of strata with tin ore, Zinwald, Bohemia . . . . 166

66. Section of tin stockwerk, Altenberg, Saxony . . . .167

67. Section of the tin stockwerk of Geyer, Saxony . . . . 168

68. Illustration of the intimate structure of the stockwerk of Geyer . 169

69. Plans and sections of tin mines on the Great Flat lode of Red-

ruth, Cornwall Plate

70. Section of tin lode at Wheal Uny, Cornwall .... 174

71. Section of tin lode at West Wheal Basset, Cornwall . . . 174

[Sections of tin lode at South Condurrow, Cornwall . . . 175

74. Plan of lode at East Wheal Lovell Mine, Redruth, Cornwall . 177

75. Section of lode imbedded in strata, South of Park Mines, Corn-

wall 178

76. Section of granite, with veins of tin ore, Cligga Point, Cornwall 1 79

77. Enlarged view of veins in granite, Cligga Point, Comvrall . . 179

78. Section of lode at Old He was Mine, Cornwall . ... 180

79. Section of the Ramraelsberg Lead Ore Deposit, Hartz, Germany 194

80. Section of strata in the Shelve Mining District, Shropshi/e . . 201

81. Section of strata, with courses of ore, at Snailbeach Mine,

Shropshire 203

82. Section of strata at Llangynog, North Wales . . . . 204

83. Cross section of the lode and workings at the Van Mine, Mont-

gomeryshire 206

84. Section in Cardiganshire, showing probable thicknesses of

mineral zones 209

85. Section of the Llanrwst Mining District, Carnarvonshire, showing

depths of several mines 213

86. Section of lode in Old Pencraig Mine, Carnarvonshire . . . 214

87. Section of West Chiverton Lead Mine, Cornwall . . • 215

88. Section of lode in Wheal Mary Ann, Cornwall . . . . 217

LIST OF ILLUSTRATIONS. XXI

PIG. PAGB

89. General section across the Pennine Chain, England . .219

90. Detailed section of limestone strata. North of England . . 220

91 . Cross section of Browngill Vein, Alston Moor, North of England 221

92. Lode in Great Limestone Vein at Cowper's Dyke, North of

England . 222

93. Piano-section of the ' Low Flat/ west of the Handsome Cross

Vein, North of England 224

94. Cross section of the same, showing the * flats ' in the Great

Limestone 225

95. Section of limestone strata, Yorkshire, showing productive and

unproductive portion of lodes 227

96. Section of limestone in Flintshire and Denbighshire . . . 230

97. Section of strata at North Hendre Lead Mine, Mold, North

Wales 231

98. Lead lode in micaceous slate, Connecticut 234

99. Lead ore deposits in galena limestone, Wisconsin . . . 236 100. Section of lead deposit, Williams & Co*s. Mine, Wisconsin . . 237 loi. Section of lead deposit. Black's Mine, Wisconsin . . . 237

102. Section of strata in California Gulch, Colorado, showing portion

of carbonate of lead deposits 238

103. Section of strata with zinc ore deposits, between Li^ and

Verviers 244

104. Diagram of the Vieille Montagne zinc ore deposit, Aix-la-

Clu^le 245

105. Section of strata with zinc ores, near Sparta, New Jersey . 247

106. Section of KunjamuUay Iron Mountain, India . . . . 254

107. Section of ironstone mine at Obemeissen, Nassau, North

Germany 256

108. Diagram of strata with iron ore, Danemora, Sweden . . . 257

109. Section of strata with iron ore, Hajrtor Mine, Devonshire . 263

1 10. Diagram of the ironstone pockets in the Forest of Dean . . 264

111. View of large ironstoue chum. Devil's Chapel, near Bream . 265

112. Section of haematite deposit at Parkside, Cimiberland . . . 266

113. Section of the Jurassic strata of England, showing the relative

position of the Yorkshire, Northamptonshire, and Lincolnshire iron ores 270

1 14. Section of Pilot Knob, Missouri 277

115. Section showing the geological position of the iron ores of Lake

Superior 278

116. Lode worked by vertical shaft 304

117. Lode worked l^ diagonal shaft 305

118. Internal arrangements of shaft 307

119. Timbering shaft in loose ground 308

XXll LIST OF ILLUSTRATIONS.

FIG. PACK

1 20. Section of shaft with man engine 309

121. Timbering level in loose ground 311

122. Timbered entrance to level 312

123. Stone entrance to level 312

124. Timbered roof of narrow working level 314

125. Timbered roof of wide working level 314

126. View of stopes in a mine ' • • 315

127. Plan of workings in the Clayband ironstone of Warwickshire . 316

128. Plan of working the Cleveland ironstone 317

129. Section of drilling machine 324

130. Boring machine at work 327

131. Hand-power rock drill at work 328

132. Section of mechanism of hand -power rock drill . . . . 329 133. ) « . . , « f Bucket hft . .346

135. Marsden*s Blake*s ore crusher 352

136. Old Cornish stamping machine 354

137. SholPs pneumatic stamping machine, side view . . 359

138. Sholl's pneumatic stamping machine, front view . . . . 360

139* y^SS^^ "^^^ movable sieve 364

^40, Jigger with fixed sieve 364

141. Continuous ore dressing machinery— elevation . . . 366

142. „ side elevation of jiggers 367

143. ,, end elevation of jiggers 368

144. Rotating huddle or jigger 369

145. Section of round buddle 370

146. Section of Silver Mill in Western America 371

147. Slaves washing for gold and diamonds in Brazil . . . 378

148. Modern hydraulic mining 379

A TREATISE ON ^^ ^., "''^l.