These rectangle stud earrings are 5/8″ by 3/8″ at their widest point. Materials: 14k gold or rose gold-fill (14k gold over brass core/no nickel) and sterling or oxidized sterling silver (.925). All materials are hypoallergenic. The black (oxidized) components of our jewelry will wear over time and eventually achieve a beautiful antique-like finish. These earrings are designed in San Francisco and handmade in our Upstate New York production studio.