Chap. XLI. ] 
CHITALDRUO DISTRICT. 
1121 
it for short the G. R. formation, 1. am inclined to believe that the 
clays were not deposited in their present condition, but merely re- 
present altered phyllitic rocks forming an integral portion of the 
Archaean schists, and hence are not to be correlated with the Kadapahs, 
which are of Pui ana age. If my doubt be sustained in this respect, then 
one must wonder if it really be a fact that there is a unconformity be- 
tween the chlorite-schist formation and the clays, which might pos- 
sibly have been formed in part by the alteration of chlorite-schists or 
-phyllites. 
Mr. Sampat Iyengar describes the G. R. formation as consisting 
of conglomerates, red ?nd white mottled clays, ferruginous clays, 
grits and sandstones, and jaspery and brecciated hematite- quartzites. 
He mentions the occurrence of lateritic caps on top of the clays and 
says that manganese occurs as nodular lumps in this laterite. He 
further says that the hematitic quartzites are often found brecciated 
and always occur associated with the red mottle clays, and that man- 
ganese-ores, chiefly pyrolusite, are found in the cavities of the 
quartzites. 1 The localities given for these hematitic- quartzites are 
the hills N. and N. W. of Jammapur ; east of Basavankote (Jagalm 
taluk) ; hills close to Bhimasamudram, and to the south of Chitaldrug. 
Mr. lyengpr also mentions the occurrence of manganese-ores in the 
clays. 
I do not propose to discuss here the origin of the ores found in this 
district, for I have seen only one deposit, namely that at Sadarhalli. 
Here the evidence seems fairly clear that the manganese and iron-ores 
have been formed by the superficial replacement and alteration of 
original quartzites and argillaceous rocks, probably phyllites. For 
details see the account of this deposit. 
The following is a list of the deposits of which I have any informa- 
tion : — 
1. Sadarhalli. 
2. Dod Kit,tadhalli. 
3. Madadkere. 
4. Nirgudda Hills. 
5. Iplara Hills. 
6. lodimaradi. 
1 Ibid., p. 84. 
