784 MANGANESE DEPOSITS OF INDIA : DESCRIPTIVE. [PaRT IV : 
bieaking pieces from the outcropping blocks over the whole of this area 
was analysed at the Imperial Institute with the following result : — 
Sample No. 12. 
Manganese peroxide .......... 22". 51 
■Nfangancse protoxide ......... 52' 42 
Ferric oxide . . . . , . . . . . . 8'8.5 
Combined silica . . . . . . . . . .10-03 
Free silica . . . . . , . . . . O'OO 
Phosphoric oxide . . . . . , . . . 0- 10 
Moisture at 100° C. . . ! 0-32 
Carbon dioxide .......... 0-41 
This is equivalent to : — 
Manganese ........... 54*98 
Iron 6-19 
Silica (total) 10-63 
Phosphorus ........... 0-044 
The high percentage of silica is doubtless an expression of the fact 
that there is a certain proportion of rhodonite in the ore. The low per- 
centage of peroxide of manganese compared with what is customary 
and the correspondingly high percentage of protoxide are also indications 
of the presence of rhodonite in fair proportion. Hence it is not possible 
to say what proportion of braunite this analysis indicates. The amount 
of carbon dioxide returned is, however, smaller than I anticipated, as 
it indicates the presence of only just over 1 per cent, of rhodochrosite. 
The large amotmt of manganese in the ore came as a surprise to me, and 
it means that the ore is of considerably better quality than one would 
suspect from its appearance. 
The following analyses were taken from the reports of Messrs. 
H. K. Scott and W. Selkirk, respectively : — 
Mr. Scott. 
Mr. Selkirk. 
Manganese 
Iron .... 
Silica .... 
Phosphorus 
56-68 
6- 21 
7- 68 
0-078 
54-20 
5-00 
9-75 
0-036 
1 Dried at 212° F. 
Mr. Scott's sample was taken from the outcrop with the rejection 
of any ore that did not look good, whilst Mr. Selkirk's sample repre- 
sented the ' general run of the ore neglecting, however, the siliceous 
portions.' 
