The cent was bronze (95 percent copper, and five percent tin and zinc) from 1864 to 1962. In 1962, the cent's tin content was removed. That made the metal composition of the cent 95 percent copper and 5 percent zinc. The alloy remained 95 percent copper and 5 percent zinc until 1982, when the composition was changed to 97.5 percent zinc and 2.5 percent copper (copper-plated zinc). Cents of both compositions appeared in that year. (us mint)
