Mining
& Processing
Mining for granite is done manually. For drilling and channeling hand
chisels and hammers are used. There are very few quarries that have mining
machinery, such as compressors and drilling machines for drilling and
blasting, cranes for lifting big blocks, and dampers and trucks for
transport.
There are, four operations that are involved in the processing of granite.
They are:
- Dressing
- Cutting/Sawing
- Surface Grinding and Polishing
- Edge-Cutting-Trimming.
Granites are now mined in most of the Indian states for use as
construction material and road metal but production of dressed granite
blocks and slabs from Andhra Pradesh, Karnataka, Rajasthan and Tamil Nadu
are highly priced. In India there are 43 granite processing units of which
12 are in Andhra Pradesh, 13 in Karnataka, 3 in Rajasthan, 14 in Tamil Nadu
and 1 in Orissa.
The recovery of marketable grade granite is reported to be 32 to 40 per
cent in Karnataka, 25 to 75 per cent in four quarries around Jalore, the
main granite mining centre of Rajasthan, and 20 to 40 per cent in Tamil
Nadu.