Beads in an necklace show a metallic appearance not seen in chalcedony.

Material from a new opal deposit in Morelia, Mexico is examined.

Chemical analysis is performed on the black core of a red grossular garnet crystal.

A large tektite found in northern Vietnam is examined in GIA’s Bangkok laboratory.

Opal was the focus of the April 2015 Sinkankas Symposium at GIA’s Carlsbad, California campus.

Ruby cabochons from mainland Europe’s only deposit are available on the market.

A large orange garnet forms a rare and beautiful inclusion in a color-change sapphire.

A London-based company aims to responsibly source emeralds from Swat Valley, Pakistan, while supporting women in business and education.

A reported untreated ruby from Mozambique shows evidence of heat treatment.

Pyrite particles included in a “black grass” red agate are unique to material from Liangshan, China, and serve as indicators of origin.

Amphibole, a collectors’ stone in its own right, is identified as an inclusion in a ruby from Mozambique.

Methodical gemological testing in the New York laboratory unmasks a cleverly-dyed beryl imitating an emerald.

Thorough testing by Carlsbad gemologists reveals an artificial glass imitation posing as moldavite.

A partially polished rock fragment exhibits a very realistic eye pattern.