Gemmological Study on Cr-Bearing Edenite

Cr-bearing edenite, just like emerald, is emerald-green, translucent to transparent, with high hardness, vitreous luster, well-formed crystal, and its single crystal size is large. The gemmological characteristics of Cr-bearing edenite are studied systematically by using UV-VIS absorption spectrum and routine gemmological techniques.In addition, the colouration mechanism is probed.It is proposed that Cr³⁺ in the crystal lattice results in the green colour.