Dollar coins have been minted in the United States in gold, silver, and base metal versions. The term silver dollar is often used for any large white metal coin issued by the United States with a face value of one dollar, although purists insist that a dollar is not silver unless it contains some of that metal. Silver dollars, the first dollar coin issue, were minted beginning in 1794. Gold dollars and gold-colored dollars have also been produced by the United States. The Sacagawea and Presidential dollars are often referred to as “golden dollars”.
In modern times, dollar coins have not been very popular in the United States. Despite efforts by the government to promote their use, most Americans currently use the one dollar bill rather than dollar coins.
Article Source: en.wikipedia.org