Tucson Gem & Mineral Show - The "Main" Tucson Gem Show
IGS - International Gem Society - Gemological organization with excellent educational program.
AGTA - The American Gem Trade Association of North American trade professionals.
Online guide to gemstone prices - First online guide to colored gemstone prices. Gemstone prices database is updated weekly. Fast and precise online gemstone appraisal. Gemval.com service is free.
Ultra Tec - Manufacturers of the world's finest faceting equipment