[cid:image001.jpg@01D7A944.192A45B0] Hear from GIA researchers on the latest topics:
Playing the Blues:
An Overview of Sapphire Treatment
Thursday, September 16 at 10:00 a.m. PDT
For almost as long as there have been gems, there have been gem treatments. The earliest description of treating blue sapphires dates to roughly a thousand years ago. Since then, sapphire treatment has evolved, and numerous new treatments have emerged that can radically alter the appearance of a sapphire. From low temperature heat treatment to beryllium diffusion and more, tune in as Wim Vertriest, Manager of Field Gemology at GIA Bangkok, explores the history, science and technique of treating blue sapphires and how to detect these treatments.
Wim Vertries is the manager of field gemology at GIA Bangkok. In his role, he oversees the field gemology department and curates GIA’s colored stone research collection.
Experiments on ruby and sapphire during the 1980s concentrated on diffusion of titanium and chromium (which are coloring agents in corundum). The ability to fully penetrate the stone with color met with little success. In 2003, very strongly colored sapphires appeared in the market, and diffusion was suspected. It was found that it was diffusion of beryllium which has a much smaller atom than titanium or chromium. Be was able to diffuse all the way through a sapphire; even large sapphires, successfully changing their color. Pictured here are untreated sapphires on the left (first group), diffused and unpolished (second group), over polished needing re-diffusing (third group), and successful diffusion treatment (fourth group). GIA “An Introduction to Gem Treatmentshttps://www.gia.edu/gem-treatment#item-9”
Recorded past GIA Knowledge Sessionshttps://www.gia.edu/knowledge-sessions-webinar
September 30, 2021 | Unusual Phenomenal Colored Stones
Speakers: Dr. Aaron Palke & Ziyin (Nick) Sun