GEM ENCYCLOPEDIA
FEATURED GEM
Ruby
Ruby is the most valuable variety of the corundum mineral species, which also includes sapphire.
THE FACTS
Traces of chromium give this red variety of the mineral corundum its rich color. Long valued by humans of many cultures. In ancient Sanskrit, ruby was called ratnaraj, or "king of precious stones."
GIA’s Guide to Gemstones: Gem Encyclopedia
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 information, a buyer’s guide, photos, videos & research.
