vii THE ELEMENTS OF ECONOMIC GEOLOGY 
CHAPTER IV 
PAGE 
ORES OF PLATINUM. . . 65 
Platinum ; qualities and distribution. Ural Mountains, South 
Africa. "British Columbia. Genesis of Platinum Ores. 
CHAPTER V 
ORES OF TIN AND TUNGSTEN . . 
Tin—Historic interest, Pneumatolytic origin. Cornish Mines, Mt. 
Bischoff. Germany, Malaysia, and Nigeria. Bolivia, Tin 
Fields in General of Preumatolytic Origin, Variations in 
Price of Tin. Tungsten—Source of Tungsten. Chinese 
Deposits. Price. 
CHAPTER VI 
ORES OF COPPER. 
Copper—qualities, uses, and price. Classification of Ores, (A) 
Primary ores,—Pneumatolytic—Rossland, South Australia, 
and Braden Mine, Chile. ILodes of Cornwall. Pipe Lodes— 
South Australia and South Africa, Disseminations, Pyritic 
Masses—Spain and Mt. Lyell. 
Secondary Ores—Secondary Enrichments—Butte, Montana, 
Over Disseminated and Replacement Bodies—Rocky Moun- 
tains, Congo. Bedded or Sedimentary Ores—Mansfeld, 
Michigan, 
Q- 
CHAPTER VII 
ORES OF LEAD, ZINC, AND SILVER . . 
Lead—its Uses. Classification of Ores, (A) Primary Ores— 
Fissure Lodes—Germany, Britain, Spain, Comstock, Re- 
placement Ore-bodies—Burma. Ores with Igneous Rocks— 
Contact Ores, Ores with Quartz-porphyry sheets—Leadville, 
Broken Hill, (B) Secondary Ores——Disseminated Ores of Mis. 
sissippi.  ““ Flats” and Ore-bodies due to Descending Solu- 
tions. Sedimentary Ores. Source of the Lead in Lodes. 
Zinc—Franklin Ores, 
Silver—Cobalt Field. 
of 
CHAPTER VIII 
ORES oF F1vE Minor MEeTALS—NICKEL, MERCURY, ANTIMONY, 
ARSENIC, BISMUTH . . : . . « 113 
Nickel—Uses and Price. Sudbury ; the Genesis of its Ores. New 
Caledonia. Gap Mine. South Africa. 
Mercury—Uses and Price. Almaden Mines ; Idria, California, 
and China. Association of Ores with Kainozoic Mountain 
Movements. 
Antimony—Distribution and Formation of Ores. 
Arsenic. Bismuth.