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Spinel
The Black Prince’s Ruby. The Timur Ruby. For centuries, spinel, the great imposter, masqueraded as ruby in Europe’s crown jewels.
Tools
Field Gemology: Building a Research Collection and Understanding the Development of Gem Deposits
With more than 90 field expeditions on six continents since 2008, GIA has accumulated over 22,000 colored stone reference samples. This extensive collection of colored stones with known origins supports GIA’s research on geographic origin determination.
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Article
2019 in Review: Diamond Trade Begins Recovery, Jewelry Retail Blooms Late, Extraordinary Auction Sales
2019: A year of ups and downs in the gem and jewelry industry, including diamonds, retail, auction sales and laboratory-grown diamonds.
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Gemstones in the Era of the Taj Mahal and the Mughals
A look at the gem ornamentation of this landmark, as well as the jewels of the Mughal dynasty.
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Star Spinel with Four and Six Rays
A cabochon displaying asterism is found to be an untreated spinel with two different stars.
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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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Quarterly Crystal: Wurtzite Phantom in Quartz
For the first time, wurtzite is found as an inclusion in gem material.
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Designs from Erica Courtney
Award-winning jewelry designer Erica Courtney presents four of her creations.
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Interview with a Kenyan Miner and Dealer
Miriam Kamau relates how she became a prominent dealer and miner.
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Rex Guo: The Science and Art of Recutting Fine Gemstones
Rex Guo describes how he sources and systematically recuts faceted stones to unlock their inner beauty.
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Unheated and Unusual Colors
Margit Thorndal of Madagascar Imports offers her perspective on the colored stone market.
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