Welcome to the GIA Laboratory

GIA is considered the world’s most trusted name in diamond grading and gemstone identification. Since 1931, GIA has been dedicated to ensuring the public trust in gems and jewelry by upholding the highest standards of integrity, academics, science, and professionalism. It is the corporate birthplace of the International Diamond Grading System™ and the creator of the famous 4Cs of diamond value – color, clarity, cut, and carat weight.

GIA’s D-to-Z color-grading scale and Flawless-to-I3 clarity-grading scale are recognized by gem and jewelry professionals everywhere. And, by extension, the GIA Diamond Grading Report, Diamond Dossier®, and Gemological Identification Report are considered the world’s premier gemological credentials.

With laboratories in New York, California, Bangkok, an additional research facility in Antwerp, 14 campuses, and more than 1,100 employees worldwide, the Institute’s diamond graders, researchers, and educators are regarded, collectively, as the world’s foremost authority in gemology. And together, they carry on GIA’s proud tradition of research, discovery, and education.