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Alexandrite
Green in sunlight. Red in lamplight. Color-changing alexandrite is nature’s magic trick.
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Cat’s-Eye Alexandrite with Unique Inclusion Pattern
Examination of a chatoyant alexandrite cabochon.
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Importance of the Secondary Market for Fine Gems
Exceptional gems that are recirculated in the gem market make an impact at the Tucson shows.
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Article
Optical Effects of Phenomenal Cabochons
Learn how the structure, inclusions and properties of some gemstones interact with light to create unusual visual effects.
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Article
Shenzhen: The Frontier of China’s Gem and Jewelry Industry
All jewelry professionals are familiar with the city of Shenzhen, a global jewelry manufacturing center and a leader of China’s fast-growing gem and jewelry industry. Join the GIA team as we tour the city and discover more about its leading jewelry brands.
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Article
The Glory of Green Gems
Green gemstones, which can uplift and heal our spirits, have been popular gem choices ever since we began to adorn ourselves with jewelry.
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Article
Gemologist’s Black Opal Ring Wows Consumer, Trade Media
GIA grad Niveet Nagpal, president and head designer of Omi Privé, showcases his love of gems and brings them to life in his designs.
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“Red” Chrysoberyl versus Alexandrite: The Impact of Elevated Chromium Levels on Color and Color-Change Properties
Overview and commentary on the 2014 Journal of Gemmology article “Purple to Reddish Purple Chrysoberyl from Brazil.”
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Record-Size Natural Moissanite Crystals Discovered in Israel
Natural moissanite crystals found in Israel has broken world records, with evidence of larger crystals in the area.
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Composite Coral Veneer Glued to Artificial Matrix
Items presented as red coral are revealed by testing to be composite coral veneers over an artificial matrix.
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Prasiolite with Inclusion Influenced by Brazil-Law Twinning
A prasiolite specimen displaying Brazil-law twinning, usually seen in the amethyst variety of quartz, is examined.
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