In 1943, the United States was in the midst of World War II. Needing to conserve copper for use in wartime munitions, the United States Mint developed a penny made of 99% steel, with a zinc coating. The steel penny was only made for circulation in 1943, and is a favorite among penny enthusiasts. This beautiful black-finished wood frame features steel pennies produced in Philadelphia(2), Denver(2) and San Francisco (1). A must-have for a die-hard penny collector.