ClIAP. IV. ] 
WAt). 
119 
Spec. No. A.221 Spec. No. A.33S 
Garbham. Kodur, 
Brovra wad. Black wad. 
Mn02 ...... 68-12 61-38 
MnO 4-14 3-59 
Fe203 7 "79 ^'80 
AI2O3 3-15 2-91 
BaO 3-29 9-53 
CaO 0-82 1-32 
MgO 0-(il 0'54 
K2O 1-18 0-Cl 
Na20 0-37 0 31 
Si02 (combined) 7-85 3-00 
Si02(free) 3-10 0-40 
Sulphur 0-016 0-048 
P2O5 0 198 0-261 
AS2O5 0-026 0-012 
CoO 0 15 0 10 
NiO Nil 0-lC 
CuO O-OI 0-05 
PbO ....... Nil Nil 
ZnO ....... 0-25 0 15 
TiOa 0-06 0-02 
Chlorine and fluorine .... Nil Nil 
Combined water (H2O) .... 7 -30 5-50 
Moisture at 100° C 1 -55 4 -35 
CO2 Nil Nil 
99-980 100-041 
Manganese (Mn) 39 -95 41 "59 
Iron(Fe) 5-45 4-10 
Silica (total) 10-95 3-40 
Phosphorus (P) 0 086 0-114 
It will be seen that both these analyses show a considerable proportion 
of combined silica. This, however, is not present in the form of braunite 
as is usually the case with Indian manganese-ores containing combined 
silica ; for the specimens appear to be homogeneous and certainly do not 
contain any visible crystalline constituent. Considering the mode of 
formation of these ores, namely by the replacement of lithomargic rock, 
or perhaps partly during the formation of the lithomarge from the original 
potash-felspar contained in the rocks associated with the manganese-ore 
deposits of this area, it seems probable that the combined silica is present 
