1150 MANGANESE DEPOSITS OF INDIA : DESCRIPTIVE. [PaRtIY: 
having been formed by the alteration of the original slaty or phyllitic 
rocks, with replacement by oxides of iron and manganese from the surface 
downwards. Another cutting showed a concretion of psilomelane about 
10 inches in diameter, situated in the clay at a depth of 17 feet below 
the surface. 
Some 200 tons of manganese-ore had been obtained from these ex- 
cavations. The stacked ore seemed to be of fairly good quaUty, and 
consisted mainly of psilomelane varying from the dull grey to the lead- 
grey variety, and often showing signs of pisolitic character. There was 
also a little wad in some pieces. 
21. Urumanjanmatti. 
This is the name of the higher ridge referred to above, on the eastern 
slope of wliich the Kanjiganagutti deposit is situated. This ridge seems 
to consist, as far as seen, of quartzite that has been partially impregnat- 
ed and replaced at the surface by oxides of iron and manganese, so as 
to produce the breccia-like mixtures of quartzite, iron-ore, and manganese- 
ore, that are so common on the outcrops of Dharwar quartzites. The 
replacement of the quartzite has taken place along a network of lines, 
so as to isolate angular residual patches of the quartzite in the darkened 
portions of the rock, which have been either impregnated with or replaced 
by iron or manganese oxides. Nowhere did I see any manganese-ore 
worth the extraction. In one place, however, there is an old iron-work- 
ing from whicli the natives of ShiddarhaUi have obtained hematite for 
their iron-furnaces. This is the excavation referred to by Mr. Slater, 1 
who was the first to notice the occurrence of manganese-ores on this 
hill. With regard to the origin of the iron- and manganese-ores of this 
hill, Mr. Slater makes the following remarks, ^ with which I cannot 
agree, however : — 
' With the exception of the presence of chalcedony, an identical mode of occur- 
rence of such quartz has been noticed in almost pure manganese. Whatever may 
be the mode of formation of the latter — and evidence points distinctly to its being 
a molten intrusion— such an origin must be ascribed to much of the laterite in the 
Shimoga District. The form of a mud lava is suggested on this hill and in the 
stream running in an E. 15 ° S. direction, one mile S. E. of ShiddarhaUi, where we 
find pebbles of quartz, ferruginous quartzite, and manganese, caught up and 
bound together in a lateritic matrix.' 
iXoc. cit., p. 23. 
^ Loc. cit,, p. 24. 
