The following is a list of the major recognized diamond institutes and laboratories used for grading, testing, and certification of diamonds:

Gemological Institute of America (GIA) - New York

American Gemological Laboratory (AGL) - New York

Gem Certification and Appraisal Lab (GCAL)

International Gemological Institute (IGI)

American Gem Trade Association - New York

European Gemological Laboratory (EGL) - New York

Hoge Raad voor Diamant (HRD) - Antwerp, Belgium

Professional Gem Sciences (PGS) - Chicago, Los Angeles

Swiss Foundation for the Research of Gemstones - Basel, Switzerland