GIA Diamond Origin Report

Each Diamond Has a Story to Tell: Know Yours with a Diamond Origin Report

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WATCH VIDEO

October Birthstone

Opal: The Gem that Contains Worlds

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: Courtesy: Rod Griffin, Australian Opal, Silverado, CA
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Research & News

Carved Fancy Dark gray diamond ring.
Lab Notes

Solid Carved Dark Gray Diamond Ring

Graphite needles create the dark gray color of a most unusual solid diamond ring carved from Canadian rough.
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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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Bicolor sapphires from Rock Creek, Montana.
Gem News International

Interesting Sapphires from Montana and Australia

Intriguing bicolor sapphires and spectacularly colored thin sapphire slabs are produced by mines in Rock Creek and Inverell, respectively.
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Brownish red staurolite crystal in ruby host.
Micro-world

Staurolite in Ruby

Conspicuous bright brownish red crystals in ruby matrix are the first recorded observations of staurolite in corundum.
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Treated and naturally colored pearls.
Lab Notes

Fluorescence Spectroscopy for Colored Pearl Treatment Screening

A nondestructive rapid screening technique uses fluorescence spectroscopy to identify treated colored pearls.
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White bavenite needles in quartz.
Micro-world

Bavenite in Quartz

Faceted quartz contains numerous unusual white radial inclusions identified as bavenite.
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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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