This black and white channel arc necklace is adjustable and measures 18.0" to 19.1/2" in length. The pendant piece measures 2.0" x 1/8" at its widest point and features three small diamonds. Materials: Sterling silver (.925), oxidized sterling silver, two 1.0mm and one 1.5mm lab-created diamonds. All materials are hypoallergenic. The black (oxidized) components of our jewelry will wear over time and eventually achieve a beautiful antique-like finish.This necklace is designed in San Francisco and handmade in our Upstate New York production studio.