Unique Star Sapphire with Transparent Core

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Three Irradiated CVD Synthetic Diamonds

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

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HPHT合成メレーの大きなバッチで発見された1つの天然メレーダイヤモンド (英語)

Over the last decade, the production methods used to create synthetic diamond melee have improved substantially, along with the quality of the specimens themselves.

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Cabochons Fashioned from the Shell of Crassostrea Virginica

Crassostrea virginica, the so-called Eastern or American oyster, is a commercial seafood widely distributed along the east coast of the United States to the Gulf of Mexico.

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Beryl and Glass Assemblage Imitating Emerald

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

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15 Carat HPHT Synthetic Diamond

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Large HPHT-Treated Blue Type IIb Diamond

A look at the color zoning exhibited by the largest HPHT-treated blue diamond graded by GIA.

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Two Natural “Horse Conch” Pearls

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

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