The Black Prince’s Ruby. The Timur Ruby. For centuries, spinel, the great imposter, masqueraded as ruby in Europe’s crown jewels.


30-Year Marine Corps Veteran Fulfills Dream of Becoming a Field Gemologist

The rigors and often-harrowing conditions of gemology field expeditions are no match for 30-year Marine veteran with a love of gems.

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The Red Hot Gems of Summer

Sharon Bohannon, August 23, 2017

These red, pink and orange-hued gems evoke passion and excitement – and are surefire accessories for sultry summer days.

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Fine Gems and Update from Myanmar

A look at top-quality gems and insight into a delegation’s visit to gem mines in Myanmar.

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Gems and Minerals from the Subarctic

Circumnavigate the boreal reaches of the globe to explore gems from polar regions.

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Synthetic Sapphire and Synthetic Spinel Doublets

Unusual doublets created from two different synthetics are revealed at the Carlsbad laboratory.

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Update on Gemstone Mining in Northern Mozambique

Recounts an expedition to Mozambique’s important deposits of ruby, spinel, and tourmaline, which have yet to be fully explored.

Etch Marks, Negative Crystals, and Etch Tubes in Spinel from Madagascar

A spinel from Madagascar, mixed in with a parcel of blue sapphire, exhibited an array of internal features.

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Seek the World’s Most Vivid Blue Spinel with GIA Field Gemologists

Join GIA’s field gemologists as they seek Vietnam’s exotic sky-blue spinel.

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Unusual Yellowish Green Spinel

A spinel in a rarely seen color is submitted to the New York lab.

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“Star of David” Spinel Twin Crystal with Multiphase Inclusions from Mogok

A rare spinel, featuring a Star of David pattern and multiphase inclusions, is examined in Bangkok.

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Found in lava, meteorites, and deep in the earth’s mantle, yellow-green peridot is the extreme gem.

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Dazzling brilliance. Captivating color. These are the planet’s most valued gems.

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Diamonds are among nature’s most precious and beautiful creations.

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Emerald is the bluish green to green variety of beryl, a mineral species that includes aquamarine.

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Citrine is the transparent, pale yellow to brownish orange variety of quartz.

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G&G Winter 2017 Edition
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