CiiAP. XXX.] 
I'ANCIl MAHALS UlSTRICT. 
653 
The accompanying sketch-map shows the spots at which I found these 
ores ; a careful examination of the hills to the east and north would doubt- 
less reveal many more such occurrences, such as that now being worked by 
the Bamankua Manganese Co. 
+ Local ities .for Mang&nesa-ore 
Figi 38.— Map of the Sivaraj[)ur iuangi!u-*e urea. 
The manganese-ores are, as far as I could tell from the field evidence 
Origin of the ores. the study of microscope sections, of superficial 
origin resulting from the replacement— more or less 
complete— of the Dharwar quartzites (and sometimes of the slates) by 
oxides of manganese. These ores, like those of the Jabalpur and Singh- 
bhum districts, are, in consequence, very irregularly distributed ; and at 
none of the outcrops examined by me did there seem to be any evidence of 
the existence of ore in quantity sufficient to be of much economic import, 
ance, with the possible exception of the occurrence (A) to be noticed below. 
Since the opening up of some of the occurrences— I believe of A and others 
on the same ridge — is said to have shown the presence of large quantities 
of ore to a depth of 40 feet, with no signs of its lessening in quantity at that 
depth, and since the ores often contain a certain quantity of braunite (see 
