CONTENTS. 
Chapter V.—History and technology of the gold deposits 
History of mining development. 
Production. 
Mining.. 
Sampling. 
Processes of reduction. 
Technical details. 
Labor conditions. 
Financial conditions. 
Extent of productive territory. 
Chapter VI.—Preliminary review of the mining industry 
Earlier work in mining geology. 
Distribution of mines. 
Extent of underground development. 
Placers.. 
Chapter VII.—Structure of the gold deposits. 
Principal types of deposit. 
Lode fissures. j. 
Distribution. 
Direction of Assuring. 
Dips. 
Persistence. 
Influence of country rock. 
Structural features. 
Intersections. 
Origin of fissures... 
Chapter VIII.—The ores. 
General character... 
Composition and value... 
Fissure fillings.. 
Mineralogy.. 
Structure.. 
Exceptional varieties of veins.. 
Lead-zinc veins. 
Celestite vein. 
Biotite-feldspar vein. 
Chapter IX.—Processes of alteration. 
■Metasomatism in connection with vein formation- 
Extent of alteration. 
Character of alteration. 
Metasomatic minerals.. 
Metasomatic changes in phonolite. 
Metasomatic changes in syenite. 
Metasomatic changes in latite-phonolite. 
Metasomatic changes in breccia. 
Metasomatic changes in schist and gneiss. 
Metasomatic changes in basic dikes. 
Metasomatic changes in granite. 
Silicification and complete replacement. 
Sequence of processes. 
Evidence of aqueous action.. 
Oxidation. 
Original water level. 
Rock oxidation. 
VII 
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