CONTENT?. XVU 
Chapter XTII. — concluded. Page. 
Formation of manganese-ores by alteration in 
situ of manganese-silicate-rocks . • . 269 
Alteration took place under oxidizing conditions . 270 
The removal of the alumina . . . .271 
The ores formed in three ways .... 272 
Ferric oxide in the ores ..... 272 
Baryta in the ores ...... 273 
Comparison with the Brazilian deposits . . . 273 
The Depths to which the Manganese-ores extend . 274 
Kaolinization ...... 274 
Oxidation 276 
The zone of fracture and belt of weathering . 276 
Ground-water level. ..... 277 
Time of formation of ores .... 278 
Depths to which the ores extend . . . 278 
Sources of the carbon dioxide .... 279 
Chaptbb XIV.— The Manganiferous Eocks of the Dharwar 
Pacies, including the Gondite Series. 
General 280 
The Dharwar period of sedimentation . . 280 
The metamorphism of the sediments . . 280 
The Transitions 281 
The Champaner series ..... 281 
The Dharwar series . . . . .281 
The Chilpi Ghat series 282 
The metamorphic and crystalline complex of the 
Nagpur-Balaghat area ..... 282 
The Aravalli series 282 
The equivalence of the various series . . 283 
' Champaner ' the prior term .... 283 
•Dharwar ' the most familiar term . • . 283 
The term • Dharwar ' adopted .... 284 
The Deposition of the Manganiferous Sediments of the 
Dharwar Period . . . . . . 284 
The soiu-ce of the manganese .... 285 
The Partial Metamorphism of the Manganiferous 
Sediments 286 
Formation of primary ores .... 286 
Localities for primary ores . . • . 287 
Formation of outcrop or recent secondary ores 
(lateritoid) ores ...... 287 
Localities for outcrop secondary ores . . 287 
