Minerals and Metals in Ancient India v2.c43.s1.t1.1

v2.c43.s1.t1.1

It is obvious that gems have been prized principally in terms of their lustre and colour. The ancient gemmologists realised that different minerals might have similar colour, and therefore identification of gem minerals involved at least one more parameter. Hardness of minerals was a very valuable guide in identification of gems, specially in view of the fact that the modern indices of evaluation such as specific gravity, refractive index, X-ray diffraction pattern, etc. were not known in the ancient days.