42 
Records of the Geological Survey of India. 
[vol. VII. 
of decomposed mica near the surface, rude shafts are sunk to the fresh and uninjured mineral, 
and excavations carried on laterally from the bottom. In a few cases also, rough horizontal 
galleries are driven in from the side of a hill. In the last methods of course artificial light is 
necessary. No precaution is taken to support the roof, and accidents are not unfrequent 
from its falling in. 
The plates of mica are generally brought to the miners’ village, and there, after being 
slightly trimmed with ordinary grass-cutting knives, (which are not particularly well adapted 
for the purpose, hut are probably the only ones the people are able to purchase,) they are 
sorted info different heaps according to quality and size. The quality depends on the mineral 
being in a perfectly unaltered condition, its transparency and freedom from cloudiness caused 
by internal foreign matter, the absence of minor cleavages which render it liable to split 
into ribbons and triangles, and the planeness of its fissile surfaces. Six kinds are recognised 
according' to the size of the plates, viz .:— 
1st. —Sanjhla. 4 th. —Karra. 
2nd. —Manjhla. 5 th. —Urtha. 
3rd. —Rasi. 6 th. —Admalla. 
Some of the minors intercalate failurtha between urtha and admalla, and speak of 
another size (barka) still larger than admalla. All these terms are used rather vaguely 
m respect to the absolute size of the plates indicated thereby. AtDhaband Jamtara I 
induced the miners to separate a quantity of the mica into the different grades, and mea¬ 
sured an average specimen of each, with the following results :— 
Dhab. 
Jamtara. 
Sanjhla 
5" x 4" 
4” X 3" 
Manjhla 
7x5 
5x4 
Rasi ... 
9X6 
6x5 
Karra 
... ... 12 x 9 
8x6 
The above four sizes include the greater portion of the mica found, it being only in the 
best mines that urtha and admalla are procurable. The largest plates I have myself seen 
measured 19" x 14” and 20" X 17" inches, hut I was informed that considerably larger ones 
are sometimes obtained. 
The mica is sold by the load, which is built up of the plates, either into one frustrum of 
a cone and carried on the head, after being hound together with cord, or into two such, and 
carried in a banghi. A load equals 6 paseris, one paseri being equal to 5 kacha sirs of 
12 chataks each, or to 3J palta sirs of 16 chataks; the load, therefore, being 221 sirs 
paka, or 4GR>s. avoirdupois. The miners informed mo that the prices paid to them by the 
mahajans were as follows:— 
Per load. 
Sanjhla 
... 
... 
... 3 annas, 
Manjhla 
... 
5 „ 
Rasi 
. . • 
7 „ 
Karra 
... 12 „ 
Urtha 
... 2 to 6 rupees 
Admalla 
the selling prices being about double the above. 
... 
... 4 to 9 „ 
The value of the large plates more especially varies greatly with the quality. I was 
informed by Colonel Boddam that plates of first quality of 18 inches diameter fetch as much 
as 60 l'upis a mand in the market, or about 30 rupis a load. 
