Creator of the 4Cs of diamond quality (Color, Cut, Clarity, Carat Weight)—GIA promotes a deeper understanding of gemstones through education, research, laboratory services and instruments. We standardized the evaluation of diamonds through the GIA International Diamond Grading System™ and our gem grading reports are accurate, unbiased and trusted by the industry and consumers alike. Today, GIA operates globally, with facilities in 11 countries and with over 3,300 employees. Discover gem news, research, and more at GIA.edu.