New Gems & Gemology Issue

D-to-Z Diamonds, Emeralds from Pakistan, a History of European Royal Jewel Sales, and More…

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New Laboratory Service

Cultured Pearl Classification Report

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January Birthstone

Garnet: From Ancient Reds to Modern Greens

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Research & News

Knowledge Rocks Week

Spring Into Color

Register for four days of continuing education seminars, a virtual alumni event and a Knowledge Rocks session.
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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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Testing of the additional exposed area on the rough stone confirmed marble.
Gem News International

Marble Imitation of Jadeite Rough

A stone submitted as rough jadeite proves upon analysis to be marble, indicative of the increasing use of imitations in the jewelry market.
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Colombian quartz with pyrite inclusions.
Micro-world

Quarterly Crystal: Pyrite in Quartz

Bright and brassy crystalline pyrite inclusions add interest to a fine specimen of Colombian rock crystal quartz.
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Notable large, unheated purple Montana sapphire.
Lab Notes

Exceptional Purple Montana Sapphire

A particularly fine unheated purple Montana sapphire is noted for both its size and its multiple diverse inclusions.
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Staurolite crystals surround a negative crystal.
Micro-world

Staurolite in a Mozambique Ruby

An unusual find of orangy red staurolite crystals appear with more expected inclusions in a ruby from Mozambique.
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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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