Gemstones and Sustainable Development Knowledge Hub

Projects developed by the GemHub to benefit miners, cutters, and others involved in the gem and jewelry industry.

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IAC Conference on Responsible Gold

Gold: Vortex, Virtues, and Values was hosted by Initiatives in Art and Culture (IAC) at Bohemian National Hall in New York City, April 12–13. Now in its eighth year, the conference has become an annual industry gathering for those looking to evaluate the market, discover exceptional work, and discuss key gold-related issues.

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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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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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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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15 Carat HPHT Synthetic Diamond

A synthetic diamond seen in the Carlsbad lab is the largest faceted lab-grown diamond examined 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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Three Irradiated CVD Synthetic Diamonds

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

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Unique Star Sapphire with Transparent Core

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

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Uncommon Parallel Color Zoning in a Chameleon Diamond

A diamond examined in the Carlsbad lab shows chameleon coloring in an unusual pattern.

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トラピッチェのようなブラジル産アメシスト (英語)

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Quarterly Crystal: Wurtzite Phantom in Quartz

For the first time, wurtzite is found as an inclusion in gem material.

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Twelve-Rayed Star Sapphire from Thailand

A black star sapphire produced from eastern Thailand, showing both golden and silver rays, is studied at GIA’s Bangkok lab.

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Microlite Crystals in Topaz from Pakistan

Aesthetically pleasing inclusions are found in topaz from Pakistan’s Shigar Valley.

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Star Spinel with Four and Six Rays

Lotus Gemology receives submissions of star stones on a regular basis, so when we first saw the specimen shown here, it appeared to be one among many of our usual stones to test.

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Perettiite-(Y) and Tusionite Inclusions in Phenakite from Myanmar

Seldom-seen inclusions are found in a host material that is rare in its own right.

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Wollastonite in Devitrified Glass Imitating Horsetail Inclusions in Demantoid Garnet

A yellowish green specimen with horsetail-like inclusions is found to be glass rather than demantoid garnet.

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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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Merelaniite Inclusions in Tanzanite

recently identified mineral is found, in whisker-like form, in a gem-quality tanzanite host.

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Natural Blue and Black Diamonds, a Byzantine Garnet Intaglio, Yogo Sapphires, and “Kasumiga Pearls”

An overview of the Summer 2018 Gems & Gemology content.

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