The GIA Laboratory-Grown Diamond Report includes full quality assessment with a plotted clarity diagram. Color and clarity specification are described on the same scale as the GIA Diamond Grading ...

Birthstones are a fun, popular and colorful introduction to the world of gemstones. They appeal to audiences around the world regardless of gender, age, nationality or religion. Birthstones carry ...

During the past 25 years, the corundum market has been transformed from one of medium to high-priced gems to one that encompasses nearly all price ranges. This transformation was caused by the ...

Adjacent amethyst and citrine colors in the same crystal of quartz have been reported from South America, although there appears to be uncertainty as to the exact locality of origin. Such material has ...

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 ...

Those born in January are lucky to have the beautiful and diverse garnet as their birthstone. Garnets are commonly red but also come in an extraordinary range of beautiful colors, including orange, ...

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 ...

A color-change sapphire was recently submitted to the GIA lab in Carlsbad for an origin determination report. The 5.68 ct transparent cushion mixed cut displayed a strong color change from grayish ...

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 ...

The best ametrines show distinct areas of orangy yellow and purple. These colors are featured in this graceful cut design. Photo by Lydia Dyer, © John Dyer & Co ...

Brazil is currently the leader in overall production of amethyst. This article describes the author's visits to three of Brazil’s most important mining areas: Marabá, Pau d’Arco, and Rio Grande do Sul ...

12月の誕生石からどれか一つを選ぶとしたら、タンザナイト、トルコ石、ジルコンのどれをお選びになりますか？青から青みがかった紫色のタンザナイト、濃い青から緑色のトルコ石、様々な色のジルコンなど、あなたにぴったりの色を見つけることが ...