AGTA 2026 HPH Desktop

Every Gem Carries A Story–
We Uncover It.

Join us for AGTA GemFair Tucson
February 2 – 6 for quizzes and prizes!

Learn More
January Birthstone

Garnet: A Palette of Rainbow Colors

January Birthstones

Learn More
Colored Stones Report Conversion

New Colored Stone Report Design

Convert existing reports for $10.
Offer ends March 15.
Limitations apply.

Learn More
FA25 GG Issue Cover

480 nm Band Diamonds, Morphology of Macle Diamonds, and White Nephrite from Russia

New Gems & Gemology Issue

READ MORE
featured

Research & News

Three loose white freshwater pearls above three strands of freshwater and akoya cultured pearls of varying sizes
Retailer Resource

Freshwater Akoyas -
A Trending Misnomer for Certain Freshwater Pearls

Small, bead-nucleated freshwater pearls marketed as “akoyas” could cause confusion and mislead consumers.
Read More

Tahitian Pearls
Retailer Resource

How GIA Analyzes Pearls from Start to Finish

Easy, step-by-step guide to how GIA analyzes pearls in its laboratory.
Read More

Starry Night
Retailer Resource

How GIA Grades Colored Stones from Start to Finish

Easy, step-by-step guide to how GIA analyzes colored gemstones in its laboratory.
Read More

Many loose laboratory-grown diamonds glowing under short-wave uv light
Retailer Resource

Testing Diamonds and Gems using UV Light

Quick how-to guide for retailers to test gemstone fluorescence and help identify stones in their own stores.
Read More

Figure 6. This selection of deep-UV fluorescence images of natural diamonds highlights the wide range of potential emission patterns and colors that can be observed, evidence of diamond’s unique growth and residence history. E: Most natural type II diamonds show blue fluorescence with mosaic-like polygonized dislocation patterns, differing from characteristic type II CVD- or HPHT-grown diamond patterns (compare with figures 8–10). Images by Garrett Koneval (A), Najmeh Anjomani (B), Wuyi Wang (C), Christopher Vendrell (D), Ulrika F.S. D’Haenens-Johansson (E), and Sandeep Kabariya (F).
Glowing Gems - What Does Fluorescence Tell Us?

G&G in a Flash: What Does Fluorescence Tell Us?

Learn about the principles, mechanisms, and characteristics of luminescence that create the impressive and memorable glow of gemstones.
Read More

CVD diamond plate and HPHT laboratory grown diamond
Laboratory-Grown Diamonds Update

The Latest on Laboratory-Grown Diamonds

Learn the latest trends by GIA on the laboratory-grown diamond industry.
Read More

Learn & Connect

Learn How To Buy

Engagement Rings

Discover

Diamond Origin

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