“Boomerang” Inclusion in a Rough Topaz

A unique twinned crystal inclusion resembles a boomerang in a rough topaz.

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Natural Diamond with Extensive Network of Etch Channels

Numerous etch channels are observed in a 5.19 ct type IIa natural diamond.

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Large Diamond Inclusion in Diamond

A fascinating diamond crystal inclusion displaying a transparent, ghost-like appearance is identified in a Faint green diamond.

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Natural Radioactivity in Select Serpentinite-Related Nephrite Samples: A Comparison with Dolomite-Related Nephrite

Uses gamma-ray spectrometry to directly measure internal radioactivity in green nephrite from deposits in Poland, Russia, Canada, and New Zealand.

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Diamonds from Guyana, Ekanite from Sri Lanka, a New Amber Source in Vietnam, and More...

An overview of the Summer 2022 Gems & Gemology content.

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A Large Aquamarine with Unusual Etch Features from Xinjiang, China

Unique natural etch pattern and dissolution cavities are observed in a large aquamarine crystal.

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Brilliance Exhibit at the Natural History Museum of Los Angeles County

A glimpse at the rare gems recently on display at the Natural History Museum of Los Angeles County’s Brilliance: The Art and Science of Rare Jewels exhibit.

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Unusual Cat’s-Eye Omphacite Fei Cui Jade

A unique jade cabochon with vivid green bodycolor and pronounced chatoyancy is examined at a lab in Shanghai.

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Smithsonian’s Great American Diamonds Exhibit

Two impressive diamonds from Arkansas and Colorado are featured in the Great American Diamonds exhibit at the Smithsonian’s National Museum of Natural History.

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The Big Find: Celebrating 50 Years of Maine Tourmaline

The historic discovery of a Maine tourmaline source is celebrated through jewelry designs featuring gems unearthed 50 years ago.

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Topaz Crystals in Red Beryl

The first report of a topaz inclusion in rare red beryl from Utah.

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Unusual Glass-and-Quartz Triplet Imitation of Emerald

An extremely convincing imitation of emerald is examined in Beijing.

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A Zircon with Strong Photochromic Effect

Photochromic zircon shows significant color change from medium light greenish blue to very dark yellowish green.

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A Gemological and Spectroscopic Study with Mobile Instruments of “Emeralds” from the Coronation Crown of Napoleon III

An examination of 45 gems from the coronation crown of Napoleon III, using nondestructive mobile spectroscopic and gemological testing methods.

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The Type IIb De Beers Cullinan Blue Diamond

GIA’s New York laboratory reports on a 15.10 ct Fancy Vivid blue cut-cornered rectangular step cut named the De Beers Cullinan Blue diamond.

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The Shape of Ekanite

Discusses the unusual surface characteristics of ekanite from secondary deposits in Sri Lanka.

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Characteristics of Newly Discovered Amber from Phu Quoc, Vietnam

Offers the first detailed summary of amber from the Vietnamese island of Phu Quoc and a comparison with Baltic, Dominican, and Burmese material.

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GIA Alumni Collective

GIA’s new Alumni Collective connects graduates around the world to foster success in the gem and jewelry industry.

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Rare Orange Benitoite

The Carlsbad laboratory reports on a large and exceptionally rare example of bright orange benitoite.

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A Reported Cassis Pearl from Key West, Florida

A unique Cassis pearl discovered in the early 1960s is examined at the Carlsbad laboratory.

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