098 
MANGANESE DEPOSITS OF INDIA : DESCRIPTIVE. [ PaRT IV 
as the accompanying phyllitic rocks, and hence occur in great quantity. 
But the exi?tence of original hematite deposits must not be assumed. 
Cases have been exposed of hematitic rocks being of superficial origin ; 
but none have yet been exposed in this state in which it would be 
considered as evident that the ores continue to any considerable 
depth. 
Foote also mentions the occurrence in the Sandur roclcs of interbed- 
ded traps, as well as intruded dvkes. All the 
Basic igneous rocks. . . i- i • i t n i 
basic Igneous rocks of which I collected 
specimens were found on microscopic examination to have once been 
plagioclase-augite-iron- ore-rocks, the iron-ore being ilmenite in most 
3ases, and probably in all. Often the rock has been converted by 
alteration into an epidiorite, with chlorite, epidote, zoisite, and uralite, 
as secondary minerals. When fairly fresh, however, the rocks could be 
termed dolerites or gabbros, according to the coarseness of grain, or 
augite-diorites, if the term gabbro be considered objectional in the case 
of a dyke-rock free from olivine. 
The plutonic granitoids and metamorphic gneissoids of Foote are 
^ J . ^ granites, gneissose granites, and gneisses, mostly 
biotitic, or with the biotite chloritized. In the 
granite of Bellary Fort Hill I found abundance of idiomorphic sphene, 
and in a gneiss from Gunda near the foot of the Ramandrug ridge, 
scattered pyrite. 
With regard to the relations of these crystalline rocks — granites, 
„ , ^. , gneissose granites, and gneisses — to the Dhar- 
K"lations oi the granites " ^ . 
and gnei.sses to the Dhar- wilrs, Foote says, referring to the writings 
ofNewboldi; — 
' The principal point on which his views < annot now be accepted is his assump- 
tion that the schistose bands in the jDeninsula have been brought into their present 
positions by being broken through by great outbursts of granite. At first sight 
this appears to be the case, but on closer and more extended examination of the 
country this idea is found to be untenable, for the old granitoids are nowhere seen 
to be irrupted into the schi.sts ; on the contrary the latter were deposited on the 
former by quiet, long-continued sedimentary action. This is of course a total 
change in the relative positions of the two rock series : the granitoids assume their 
true position as the true fundamental rocks of the country, and the schists are 
seen to be vastly younger in age than Newbold supposed them to be. 
1 Loc. cit, p. 22. 
