Following up on Nassau's 1981 article on the technical aspects of heat treating ruby and sapphire, the author reports his personal observations of the actual heat treatment process in Bangkok. He ...

Laser sawing of diamonds is beginning to revolutionize the diamond-cutting industry. Not only does the laser saw offer savings in time and money, but it also enables the cutting of material virtually ...

Synthetic emeralds grown hydrothermally in an alkali-free, chlorine-bearing solution have been manufactured in Guilin, China, since 1987. Diagnostic microscopic features include growth and color ...

Since Robert Crowningshield's discovery in the late 1950s that diamonds that have been artificially colored by irradiation and subsequent annealing could be identified by their characteristic ...

Straight, acicular, colorless solid inclusions in demantoid garnet from the Ural Mountains of Russia were investigated by laser Raman microspectrometry. These “needles,” which occur in association ...

The world's first commercially available synthetic cat's-eye alexandrite chrysoberyl is now being manufactured and marketed by the Kyocera Corporation in Kyoto, Japan. Kyocera markets synthetic ...

CARLSBAD, Calif. – April 7, 2025 – In response to logistics challenges related to recently announced tariffs affecting global shipments of gemstones, GIA (Gemological Institute of America) will ...

A synthetic gem material is one that is made in a laboratory, but which shares virtually all chemical, optical, and physical characteristics of its natural mineral counterpart, though in some cases, ...

提到摩根石的名称，就立即令人联想到美丽淡雅的粉红色、紫粉红色和橙粉红色。 - Robert Weldon（罗伯特·韦尔登），Mayer & Watt, Maysville 友情提供，肯塔基州 摩根石作为一种颜色柔和淡雅的宝石而 ...

Diamonds have a long history as beautiful objects of desire. In the first century AD, the Roman naturalist Pliny stated: “Diamond is the most valuable, not only of precious stones, but of all things ...

This jadeite "Peiyao" (Chinese Fu dog) represent mythological creatures that guard and protect celestial palaces and entrances. - Gift of Sophie Leu Jade has been cherished for thousands of years.

This sapphire from Kashmir has an intense velvety blue color. – Photo: Robert Weldon/GIA. Sapphire is one of the Big three of jewelry colored gemstones—the other two are ruby and emerald. A durable ...