This J post earring is sold individually, measures 3/8″ by 3/8″ at its widest point. Materials: 14k gold-fill (14k gold over brass core/no nickel), sterling silver (.925), or oxidized sterling silver. 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 were designed in San Francisco and are handmade in our Upstate New York production studio.