The composition of a circulating United States penny has changed multiple times since its first minting in 1793. As of 1982, the U.S. penny, also known as the Lincoln cent, is made of 97.5% zinc and 2.5% copper. This means the copper plating on the outside of each penny constitutes only 2.5% of its total metal content.
From 1962 to 1982, however, pennies were composed of 95% copper and 5% zinc. The shift to mostly zinc was due to the rising cost of copper. Despite this change, the circulating penny retains its characteristic copper color because of the thin layer of copper on its surface.
