Please visit these important members of the fine jewellery industry:

Gemological Institute of America
Established in 1931, GIA is the world’s foremost nonprofit institute of gemological research and learning. GIA discovers, imparts, and applies gemological knowledge to ensure the public trust in gems and jewelry. With over 800 employees, the Institute’s scientists, diamond graders, and educators are regarded, collectively, as the world’s foremost authority in gemology.(edited from GIA website)
International Society of Appraisers
The International Society of Appraisers (ISA) provides education and organizational support to its members, and serves the public by producing highly qualified and ethical appraisers who are recognized authorities in professional personal property appraising.
(edited from ISA website)