Explores eclogitic diamonds, which make up a significant portion of the gem diamond market, and what they reveal about Earth’s dynamic processes.

The Carlsbad laboratory recently had the chance to examine a 4.60 ct cushion-cut zircon with truly unusual color behavior.

Creative faceting highlights an octahedral-shaped cloud inclusion in a 2.01 ct diamond octahedron.

The Tokyo lab examined a stunning double cat’s-eye emerald whose chatoyancy was created both by its cut and its inclusions.

This is the second part in a three-part series on the origin of color in gem materials.

An emerging corundum deposit in northeastern China is discussed.

At the GIA Carlsbad laboratory, the authors recently examined a cabochon of “bloodshot” iolite (containing red, eye-visible platelets of hematite) intergrown with a sunstone.

Copper-bearing gem tourmaline, known as Paraíba tourmaline after the location of its original discovery, is prized for its vivid blue to green color. This article explains GIA’s use of quantitative chemical analyses to distinguish samples from Brazil, Nigeria, and Mozambique.

Each level of the vertical Hidden Gems exhibit offers a different theme at the San Diego Natural History Museum.

The Hong Kong laboratory recently examined a Burmese star ruby incorporating a significant amount of bismuth glass.

X-ray computed microtomography reveals the internal features of pearls with great detail.

In the early 1960s, French ceramist and engineer Pierre Gilson succeeded in growing and producing flux synthetic emerald of commercially marketable quality.