crystalline
and metamorphic rocks in the Nellore district; near Sankaridrug, Salem
district; near Konibetta in the Nilgiris. Brownish red to deep red or
pink garnets are obtained near Mel Amathur, Tinnevelli district and
small garnets of a rich colour are obtained in Travancore.
Rajputana
has garnet mines along the outcrops of the Aravalli schists, which are
traversed by granites and between the Udaipur and Jaipur States. A
large trade once existed between the mines and Delhi. Garnet is also
obtained at Ajmer, Jaipur, Kishengarh and Shahpura. The Kishengarh
garnets are said to be the finest in India. Ceylon also produces a lot
of almandine or gem garnets.
Industry
Rajputana
garnets are often of gem quality and are mined intermittently. The
stones are cut in Jaipur and Delhi, where gem-cutting forms an
important industry. A portion is also exported and goes to London. The
Warangal garnets were sent to Madras and also to Europe. Tinnevelli
garnets are mostly used for abrasives.
Marketing and future trend
Gem
garnets form cheap precious stones and can always find a fair market.
The inferior garnets could find a market when the indigenous abrasive
industry is gradually developed.
Chapter XVIII TOURMALINE
Introduction
TOURMALINE is a boroalumino-silicate of very complex composition. It crystallizes in the rhombohedral-hemi-morphic
system being different at the two ends of the crystals. The crystals
form curved triangular prisms! The
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