United States commemorative coins consist of coins that have been minted to commemorate a special event, person or organization of historical nature. Collectors today often refer to U.S. commemorative coins minted from 1892 - 1954 as Early Commemoratives, and those minted after 1982 as Modern Commemoratives. Many coin collectors consider the 1848 2 1/2 dollar gold piece to be the first U.S. commemorative coin, commemorating the discovery of gold in California.
Highly collected today, the State Quarters program that began in 1999 and produced five different commemorative quarters to be placed in circulation each year, with reverses for each of the 50 States in the order of their admission to the union. In 2007, six quarters commemorating the District of Columbia, two commonwealths, and four territories were added to the program for issue later in 2009.