Provides a visual guide to the internal features of natural, synthetic and treated rubies.
Read MoreAmber samples were heat-treated, using various procedures and parameters, in an effort to reproduce materials found in the jewellery market.
Read MoreAn examination of the gemmological and spectroscopic properties of CVD synthetic diamonds from Gemesis Corp.
Read MoreKnowledge of type allows gemmologists to better evaluate if a diamond might be treated or synthetic, and whether it should be sent to a laboratory for testing.
Read MoreModern gemmologists and diamantaires are faced with a broad spectrum of colour and clarity treatments ranging from the simple to the highly sophisticated.
Read MoreThe Diamond Trading Company (DTC) Research Centre had the opportunity to examine a diamond that, on submission to a commercial gem laboratory, turned out to be a coated pink diamond.
Read MoreChameleon diamonds are among the rarest of gem diamonds.
Read MoreUsing a multi-step process, Lucent Diamonds has developed a new treatment process for certain natural diamonds that creates colours from pink-purple to red to orangey brown.
Read MoreA new chart, supplementing the one published in the Winter 1995 issue of Gems & Gemmology, summarises the features of both as-grown (“non-modified”) and treated (“modified”) synthetic diamonds currently in the gem market.
Read MoreThe heat treatment of corundum involving lattice diffusion of beryllium (Be) at temperatures over 1800°C has become a major issue in the gem trade.
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