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Gems & Gemology

Fluorescence of Blue Amber from the Dominican Republic, Mexico, Myanmar

READ MORE

New Gems & Gemology Issue

Pink Sapphires from Madagascar, Antique Rose-Cut Colored Stones, and Blue Amber Origin

READ MORE

April Birthstone

Diamond: A Colorful Twist to the April Birthstone

LEARN MORE
: Courtesy of Sothebys
featured

Research & News

The Julian deposit produces emerald clusters (shown) as well as single crystals.
Gem News International

New Emerald Locality in Southern California

An emerald containing an unusual citrine inclusion heralds a new pegmatitic deposit in the Julian Mining District in San Diego County.
Read More

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.
Learn More

Face-up view of a green-yellow round brilliant diamond.
Lab Notes

Blue “Graining” in Green-Yellow Diamond

Unusual color zoning likely indicates multiple treatments of a Fancy Intense green-yellow diamond.
Read More

Bands of particles and short iridescent needles.
Micro-world

Inclusions in Kenyan Rubies from the John Saul Mine

Very similar inclusion scenes featuring needles and thin films make rubies from Kenya hard to distinguish from Mogok rubies.
Read More

Press Release

Study of Rare Diamonds Unlocks More of Earth's Secrets

Scientists at GIA continue to delve deep into earth's geologic history, using diamonds' distinctive characteristics to go – virtually – where no scientist has ever gone.
Read More

Near-colorless diamond found at the Crater of Diamonds State Park in Arkansas.
Lab Notes

Large Type IIa Diamond from Arkansas, USA

A surprising find from Crater of Diamonds State Park reveals a natural diamond remarkable in both size and clarity for its U.S. origin.
Read More


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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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