The gold dollar or gold one-dollar piece is a gold coin that was struck as a regular issue by the United States Bureau of the Mint from 1849 to 1889. The coin had three types over its lifetime, all designed by Mint Chief Engraver James B. Longacre. The Type 1 issue has the smallest diameter (0.5 inch =12.7mm) of any United States coin minted to date.
A gold dollar coin had been proposed several times in the 1830s and 1840s, but was not initially adopted. Congress was finally galvanized into action by the increased supply of bullion caused by the California gold rush, and in 1849 authorized a gold dollar. In its early years, silver coins were being hoarded or exported, and the gold dollar found a ready place in commerce.