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Natural inclusions are visible when the assemblage is viewed face-up.

Beryl and Glass Assemblage Imitating Emerald

Tyler Smith and Augusto Castillo, August 9, 2018

An unusual assembled stone is examined at GIA’s New York lab.

Rare Faceted Wurtzite

Amy Cooper and Nathan Renfro, July 25, 2014

A stone submitted for identification is revealed to be the first wurtzite examined by the GIA lab.

Two Natural “Horse Conch” Pearls

Bona Hiu Yan Chow, August 9, 2018

Rare pearls, along with their shell, are studied in the Hong Kong lab.

Unique Star Sapphire with Transparent Core

Yusuke Katsurada, August 9, 2018

A sapphire cabochon with an unusual appearance is seen at GIA’s Tokyo lab.

A Repaired Diamond

Troy Ardon, August 9, 2018

A marquise-cut diamond is found to have been broken and reassembled with an unknown adhesive.

Three Irradiated CVD Synthetic Diamonds

Sally Eaton-Magaña, August 9, 2018

Irradiated CVD-grown diamonds are examined in the Carlsbad lab.

A Cat’s-Eye Rock Consisting of Jadeite and Amphibole

Bona Hiu Yan Chow, August 9, 2018

Raman spectroscopy reveals that a green bead, showing chatoyancy on one side, comprises jadeite and amphibole.

An exceptionally large and clean 1.91 ct faceted oval brilliant afghanite.

Large Faceted Afghanite

Hollie McBride, August 9, 2018

A report on the largest facet-grade afghanite seen in the GIA gem identification department.

HPHT-treated blue diamond (left) with ragged-looking graphitization around an inclusion (center) and high-order interference colors with crossed-polarizing filters (right).

Large HPHT-Treated Blue Type IIb Diamond

Evan M. Smith, Paul Johnson, and Kyaw Soe Moe, August 9, 2018

Properties of, and theories on colour zoning exhibited by, the largest HPHT-treated blue diamond graded by GIA.

Within a parcel of 1,102 diamond melee, 1,092 were identified as HPHT synthetics.

One Natural Melee Diamond Found in Large Batch of HPHT Synthetic Melee

Stephanie Persaud, Wuyi Wang, Paul Johnson, and Ivana Petriska Balov, August 9, 2018

A single natural diamond is found within the largest percentage of undisclosed synthetic melee submitted to GIA.

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