Distance Education

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August Birthstone

Peridot: A Gem with Extraterrestrial Origins

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AI to Revolutionize Diamond Clarity Grading

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Research & News

Crowded booth at AGTA gem show.
Gem News International

Tucson 2020 Overview

An overview from the 2020 Tucson gem shows.
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Knowledge Session Webinars
Webinar Series

GIA Knowledge Sessions

Engage in webinars on the most diverse and pressing issues in gemology today, including gemstone origin, laboratory-grown stones and new discoveries in field gemology.
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Angular milky cloud shows spectral colors.
Micro-world

Phenomenon Resembling Play-of-Color in Sapphire

Subtle tilting of the unheated sapphire revealed a noteworthy phenomenon resembling play-of-color, which is most commonly seen in precious opal.
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The “Matryoshka” Diamond has an internal open cavity.
Lab Notes

Formation of the “Matryoshka” Diamond from Siberia

A freely moving diamond crystal completely enclosed in a diamond from Siberia gets its name from the famous Russian nesting dolls.
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Two blue sapphires side-by-side
Feature Article

G&G Announces Most Valuable Article Awards

G&G announces the winners of the Dr. Edward J. Gübelin Most Valuable Article Awards for 2019.
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Dyed bovine bone carving.
Gem News International

Carvings from Bali

Balinese carvers using traditional methods create striking pieces from Australian opal as well as unusual materials such as mammoth tusk and bovine bone.
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Gems & Gemology
This Month's

Featured Gems

Featured Gem Peridot
Peridot

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

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

Diamonds are among nature’s most precious and beautiful creations.
Emerald Bluish Green Stone
Emerald

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

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

View the Gem Encyclopedia

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