GEOJAKJICAL (KIOUURKNCK OF C!()AL IN INDIA. 
5 
shales and red or green clays. They are frequently unconformable 
to the Rarakais. 
Overlying the Daniudas conies the Panchet scries, which has a 
maxiniuni thickness of 1,800 feet and is com- 
c ancio rocis. p^g^^j coarse, white, or greenish-white, fcls- 
pathic, and micaceous sandstones, the felspar of which is usually 
undeconiposed. Bands of red clay are interspersed through the 
sandstones. The Panchet rocks are, as a rule, distinguished from 
the Damudas by the presence of red clay, the absence of coal 
or carbonaceous shales and the usually more micaceous character 
of the sandstones. 
In general the coal of peninsular India may be described as a 
laminated bituminous coal, in which dull and 
(•lianwUi- of Da- ij^.jg^^t layers alternate. Much of it does not cake 
muda coal. o j 
freely, while a not inconsiderable portion will 
not do so at all. However, from the coal of particular seams in the 
Raniganj, Karharbari and Jharia fields, fairly good qualities of coke 
can be made. In the Raniganj field the best coke has been made from 
the Sanctoria coal and in the Jharia field from Nos. 14, 15 and 17 
seams. The percentage of ash in Bengal coal which is brought to 
market averages from 10 to 15, that is to say that coal with less 
than 10 per cent, of ash does not commonly occur, and coal with 
more than 15 per cent, does not, as a rule, find a ready sale. In 
the producing fields of Hyderabad, the Central Provinces, and Cen- 
tral India the ash content is much higher, particularly in the latter 
provinces, where the percentage varies from 15 to 25 per cent. 
As regards the proportion of fixed carbon, which is the most 
important factor in the production of heat, the average in the 
Raniganj field is under 55 per cent., while in the Karharbari and 
Jharia fields it is probably about 10 per cent, higher. There is no 
case of a true anthracite having been discovered in any of these 
fields ; but the crushed and powdered coal at the foot of the Dar- 
jiling Himalayas approximates in character to anthracite on account 
of the removal of its original volatile constituents. 
The moisture or hygrometric water varies a good deal in the 
coals from the different fields. In those of the Godavari and 
Wardha areas it is exceptionally high, being often 14 per cent., 
while in the Raniganj field it varies^ from 1 per cent, in the 
1 Saise, Rec, Geol. Suro. Ind., Vol. XXXI, i)t 2, )3p. 10-1-107 (1904). 
