G82 
MANGANESE DEPOSITS OF INDIA : DESCRIPTIVE. [PaRT IV 
The winchite-bearing rocks were no doubt formed during the folding 
bs' the metamorphism of impure calcareous sediments containing a 
certain proportion of manganese. 
Interesting points to notice are the abundance of apatite and the pres- 
ence — though usually in small quantities — of felspar, in the spessartite- 
and rhodonite-bearing rocks. 
In Plate 19 is shown a rough sketch-plan of the deposit for the pur- 
Nature and 11 ua- pose of indicating the position of the various cross- 
lity of the ores. cuts. At about A there is a constriction or waist 
to the ore-mound, and it is a curious fact that the ore is of two different 
characters north and south of this waist. That south of the waist is 
mainly a very fine-grained mixture of psilomelane and braunite with no 
signs of spessartite or rhodonite ; according to Mr. H. J. Winch, the 
manager of the deposit, the ore shipped from this part of the deposit 
(in 1905) has the following average analysis : — 
Limits. 
Me in. 
Manganese ...... 
Iron ....... 
Silica ....... 
Phosphorus. ..... 
Baryta ...... 
Moisture under ..... 
46-4S 
8-9 
6-9 
0-08-0-25 
3 4 
0 17 
3* 
0-25 
A sample taken by me, representing 1,550 tons of manganese-ore 
from the deposit south of the waist, was subjected to complete analysis 
by Messrs. J. and H. S. Pattinson, with the following result : — 
Sample No. A.39. 
Manganese peroxide . . . . . . .50-82 
Manganese protoxide . . . . . . .20-19 
Ferric oxide . . . . . . . . ] 2 • 29 
Alumina . . . . . . . . .0-85 
Baryta . . . . . . . . .4-14 
Lime 1-40 
Magnesia 0-80 
Potash 0-74 
8oda 0-27 
Silica (combined) . . . . . . .5*15 
Silica (free) . . . . . . . . 1 • 45 
Suli)hur 0-030 
Phosj)horic oxide ....... 0 378 
Arsenic oxide ........ 0-055 
