Garnet

The Tucson 2015 Gem Show demonstrated that there are considerably more options than just the big three (ruby, sapphire and emerald) for buyers seeking fine quality gemstones. The availability of bigger and higher quality garnets in a range of colors, …

Co-Glass and Sapphire Composites

During a December trip to the 2012 GIT Conference in Bangkok, Thailand, the author purchased several blue stones claimed to be (Cobalt) Coglass filled sapphires. General observation seemed to confirm the blue sapphire color with a fairly transparent look. Microscopy …

Contemporary Jadeite Testing

Jadeite is a sodium aluminum silicate mineral which has a polycrystalline structure. The hardness is 6.5-7 on the Mohs’ scale, the average specific gravity value is 3.33, and the refractive index is approximately 1.66. The various colours of Jadeite are …