As (Roman coin) as, the (2), (2), . After the as had been issued as a cast coin for about seventy years, and its weight had been reduced in several stages, a as was introduced (meaning that it weighed one-sixth of a pound). At about the same time a silver coin, the denarius, was also introduced. Earlier Roman silver coins had been struck on the Greek weight standards that facilitated their use in southern Italy and across the Adriatic, but all Roman coins were now on a Roman weight standard. The denarius, or 'tenner', was at first tariffed at ten asses, but in
Dollar coin (United States) Dollar coin (United States) The dollar coin is a United States coin worth one United States dollar. It is the second largest U.S. coin currently minted for circulation in terms of physical size, with a diameter of 1.043 inches (26.5 mm) and a thickness of .079 inches (2 mm), coming second to the half dollar. Dollar coins have been minted in the United States in gold, silver, and base metal versions. Dollar coins were first minted in the United States in 1794. The term silver dollar is often used for any large white metal coin issued by the United States