These gorgeous stud earrings are made with genuine Swarovski Crystal Elements in Aurora Borealis (Crystal AB) Crystal color. Studs measure 6mm in diameter and 1 CTW each for a total carat weight of 2 CTW. Your choice of gold plated or silver plated with surgical steel posts. Made here in the U.S.A and Tourmaline Opal (similar to Crystal AB) is the birth stone color for October!