IGI Certified 18k White Gold 3-Prong Round Diamond Stud Earrings (3/4 cttw, G-H Color, SI1- SI2 Clarity) Classic stud earring in 18k gold with dazzling diamond round and screw backing for added security IGI-certified jewelry has been assessed and authenticated by the International Gemological Institute's expert gemologists. All our diamond suppliers confirm that they comply with the Kimberley Process to ensure that their diamonds are conflict free. Domestic Carat weight listed is the total for both studs.