About GIA

Established in 1931, GIA is the world’s largest and most respected nonprofit institute of gemological research and learning. Because diamonds are so valuable, GIA believes it is essential for industry professionals to have a universal grading system when comparing diamond quality. It is out of this need that in the mid-twentieth century, GIA developed the International Diamond Grading Systemú and the 4Cs as a way to objectively compare and evaluate diamonds.

GIA discovers (through GIA Research), imparts (through GIA Education), and applies (through the GIA laboratory and GIA Instruments) gemological knowledge to the public. With 1,200 employees, the Institute’s scientists, diamond graders, and educators are regarded as the world’s foremost authorities in gemology.

Internationally, the Institute has distinguished itself as the preeminent source of gemological knowledge and professionalism. The GIA Diamond Grading Report and the GIA Diamond Dossier® are considered to be the world’s premier credentials of diamond quality. Many retailers provide diamond certification, however no report is as unbiased and complete as a GIA diamond grading report. Diamonds of all shapes and sizes are sent to the Institute from every corner of the globe for diamond grading and analysis.

Some famous diamonds have been graded by GIA including the Hope Diamond (45.52 carats), the Steinmetz Pink (59.60 carats), the Taylor-Burton (69.42 carats), the Allnatt (101.29 carats), the De Beers Millennium Star (203.04 carats), the Centenary (273.85 carats), and the Incomparable (407.48 carats).

Today, GIA’s D-Z color-grading scale, Flawless-I3 clarity-grading scale and Excellent-to-Poor cut-grading scale are recognized by virtually every professional jeweler and savvy diamond buyer in the world.