All diamonds are rare and no two diamonds are alike. A diamond’s quality and rarity is determined by its unique combination of characteristics of Color, Cut, Clarity and Carat Weight. The International Diamond Grading System™, used around the world since its invention by GIA in the 1950s, is based on the Four Cs. (more…)
GIA does more than set the integrity standards in the gem and jewelry industry. We provide research, lab services and educate gemologists from around the world. In this 6-minute video, Bev Hori, GIA education director, explains the global impact of GIA, giving you a broader view of what we do in Carlsbad, CA. (more…)
As you’ve searched for the perfect diamond, you may have learned about high pressure/high temperature diamonds, or HPHT. These are diamonds that have been treated via temperature or pressure to look better than they were naturally. Jewelers are required to provide full disclosure on HPHT stones to their customers. (more…)
My grandfather was a client of GIA’s back in the 50s and early 60s. He died only a few years after I was born, but at his company in Long Island City, New York, where both my mother and father continued to work, I grew up surrounded by the tools of an amateur gemologist—which only stopped gathering dust when my sister and I handled them (secretly, so mom wouldn’t yell). (more…)
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