Most Russian hydrothermal synthetic rubies and pink, orange, green, blue, and violet sapphires—colored by chromium and/or nickel—reveal diagnostic zigzag or mosaic-like growth structures associated ...
Each year basalt-topped Peridot Mesa, on the San Carlos Apache Reservation, is a major source for thousands of carats of gem-quality peridot in sizes suitable for use in modern jewelry. Marketed ...
Amethyst may develop into the more common citrine and rarer green quartz naturally under certain geologic conditions. On the California-Nevada border, just north of Reno, amethyst, citrine, and green ...
ルビー、サファイア、エメラルド、パライバ トルマリン、レッド スピネル、アレキサンドライトが、GIAカラー ストーン鑑別及び原産地レポートの対象となります。しかしながら、これはGIA ...
Some results have been hidden because they may be inaccessible to you
Show inaccessible results
Feedback