The Australian Threepence was a small silver coin used in the Commonwealth of Australia prior to decimalization. It was minted from 1910 until 1964, excluding 1913, 1929 - 1933 inclusive, 1937, 1945 and 1946. After decimalization on 14 February 1966, the coin was equivalent to 2½¢, but was rapidly withdrawn from circulation.
During World War II, between 1942 - 1944, threepence production was supplemented by coinage produced by the United States Mint with coins produced at the San Francisco and Denver mints. Coins minted at the San Francisco mint 1942-1944 contain a small S on the reverse, while coins produced at the Denver mint 1942-1943 have a small D on the reverse.