GEM ENCYCLOPEDIA
FEATURED GEM
Opal
Fireworks. Jellyfish. Galaxies. Lightning. Opal's shifting play of kaleidoscopic colors is unlike any other gem.
THE FACTS
Opal's microscopic arrays of stacked silica spheres diffract light into a blaze of flashing colors. An opal's color range and pattern help determine its value.
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.
