GIA’s Gem Encyclopedia is a virtual journey through the science and lore of gemstones from across the globe. Each precious stone page features additional detailed gemological …

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. …

After a systematic study of natural diamonds, laboratory-grown diamonds, colored diamonds and diamond simulants we determined the differences to ensure accurate stone identification.

An Identification Report, with geographic origin added. For polished, loose or mounted natural alexandrite, emerald, jade, Paraíba tourmaline, red spinel, ruby, and sapphire only.

The GIA iD100 ® combines advanced spectroscopic technology with GIA's 60 years of diamond and gemstone identification research to distinguish natural diamonds from laboratory-grown …

Gem Identification Practice procedures and skills to identify a wide range of natural, synthetic and imitation gemstones. Learn More

The GIA Identification Report describes whether the stone is natural or laboratory-grown, identifies the type of gemstone, and includes any detectable treatments.

To view fees, chose your gemstone type and currency. All new Fees Effective September 1, 2025* Natural D-to-Z Diamonds U.S. Dollar Botswana Pula South African Rand Indian Rupee …

Alexandrite Gemstone is a rare variety of the mineral Chrysoberyl & is a strongly pleochroic gem. Color-changing alexandrite is nature’s magic trick.

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