Gems & Gemology

Low-Temp Heating of Pink Sapphires from Madagascar

READ MORE

May Birthstone

Emerald: Treasures Hailing from Colombia to Afghanistan

LEARN MORE

Gems & Gemology

Rose-Cut Colored Stones from the Seventeenth Century

READ MORE
featured

Research & News

Oiling the fissures dramatically improves the appearance of this tanzanite.
Gem News International

Oiled Tanzanite

A large tanzanite loses its appeal with the removal of its fracture-filling oil.
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

DIAMONDS FROM THE DEEP

What Have Diamond Ages Taught Us?

Diamond ages offer insight into continent evolution spanning billions of years.
Read More

Raman identified this crystal as “high” zircon.
Micro-world

Zircon in Jadeite Jade

A doubly terminated zircon inclusion survives multiple treatments in a translucent bangle of jadeite jade.
Read More

A bracelet and two seal stamps made from resin imitation ivory.
Gem News International

Spectral Analysis of Resin Imitation Ivory

Spectroscopic techniques prove key in separating resin-based imitation ivory from natural ivory.
Read More

Purplish pink Montana sapphire in this study (left) next to a hexagonal rough (right).
Lab Notes

Rare Intense Purplish Pink Montana Sapphire

A Montana sapphire of unusual size and color proves to be from the secondary deposit of Rock Creek.
Read More

Learn & Connect

Learn How To Buy

Engagement Rings

Start A Career

in Gems & Jewelry

Use our labs to

Verify a Stone

Download

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

You Might Also Like

Find a Retailer
learn more
Shop the Campus Store
Learn More
Abstract art with fluorescent rainbow and dark brown triangle patterns
Subscribe to Knowledge Rocks Emails
Learn More
G&G Winter 2020 Edition
Learn more