Coast to Coast Rare Stones - Sister site to johnjbradshaw.com; Find all your rare and collectible gems here.
Alpine Gems - The "Canadian Gemstone" site from Brad Wilson, one of the Coast to Coast team.
GemDat-org - New site with great info and pictures of all types of gemstones.
AGTA - American Gem Trade Organization
GIA - Gemological Institute of America
ICA - International Colored Gemstone Association
Gem-A The Gemmological Association of Great Britain
The Guide - GemWorld International publishes pricing information available to the gem trade.
Roskin Gem News Report - A great online report of the happenings in the gem world by Gary Roskin
Gems & Gemology (G&G) - One of the world's best gemological publications from GIA
Smithsonian Institution - United States National Museum
Harvard University - Beautiful New England Museum housing a fabulous collection of both gems and minerals
Tower of London - Home of the British Crown Jewels