ගෙවුඩ තාප පිරියම්කරණය පිළිබඳ දැනුවත් කිරීමේ පෝස්ටරය
(Classifications of Mineral Corundum Found In Sri Lanka.
Gem and Jewellery Research and Training Institute)
Sri Lanka, the "Island of the gems" is blessed with plenty of gem minerals and
considered as the single most important source for fine gemstones. Sri Lankan
gem beds has contributed for 17 of 20 largest blue sapphires in the world. In
addition, different types of low quality translucent corundums commonly known
as "geuda" are also found more often in the Sri Lankan gem gravel, giving rise to
a large array of varieties. The main significance of these varieties is the possibility
to enhance their colour and clarity by heat treatment.Here, a novel systematic
classification for all corundum varieties found in Sri Lankanterrain is introduced,
based on their physical, optical, and chemical properties. In this, the "geuda"
are considered as a variety of corundum and classified based on the amount of
rutile (TiOz) impurities with light scattering effect or "brownish tint" in the mineral
which is the common practice in the trade.
Price :
* Student – Rs. 750/-
* Others – Rs. 1000/-
|