CONTENTS. 25 



Chapter XII. — The Relations of Metamokphism to Ore Deposits — Continued. Page. 

 Part II. Segregation of ores — Continued. 



Division C. Ores produced by processes of metamorphism — Continued. 

 Group B. Ores deposited by aqueous solutions — Continued. 



III. Work of aqueous solutions in segregating ores— Continued. 



Subclass 1. Ores precipitated from ascending aqueous solutions — Cont'd. 



Compounds deposited by ascending solutions 10S8 



Metals 1089 



Gold 1089 



Solution 1089 



Precipitation 1091 



Silver 1099 



Solution 1099 



Precipitation 1100 



Copper 1101 



Solution 1101 



Precipitation 1101 



Sulphides : 1104 



Solution of sulphides 1106 



Precipitation of sulphides 1108 



Precipitation of sulphides transported as such 1109 



^Precipitation of sulphides transported as oxidized salts. 1110 



General statements 1117 



Tellurides 1119 



Oxides 1125 



Magnetite 1126 



Zincite 1126 



Franklinite 1126 



Hematite 1126 



Cassiterite 112V 



Carbonates 1128 



Silicates 1129 



Criteria for discriminating deposits of the deep circulation 1132 



General statements 1138 



Subclass 2. Ores precipitated from ascending and descending aqueous 



solutions 1139 



Association of lead, zinc, and iron compounds 1144 



Facts of occurrence 1144 



Second concentration 1147 



Oxidized ores 1147 



Sulphide ores 1148 



Galena 1148 



Sphalerite 1151 



Marcasite and pyrite 1152 



General statements 1153 



