Sestertius Sestertius The sestertius (plural sestertii), or sesterce (plural sesterces), was an ancient Roman coin. During the Roman Republic it was a small, silver coin issued only on rare occasions. During the Roman Empire it was a large brass coin. The name "sestertius" means "two and one half", referring to its nominal value of two and a half "asses" (a bronze Roman coin, singular "as"), a value that was useful for commerce because it was one quarter of a denarius, a coin worth ten "asses". The name is derived from "semis", "half" and "tertius", "third", in which "third" refers to the
Hong Kong ten-cent coin Hong Kong ten-cent coin The ten-cent coin is the lowest-denomination circulating coin of the Hong Kong dollar. With a diameter of 17.5 mm and a mass of 1.85 g it is also the smallest in size and weight. It is the oldest coin denomination to still be in circulation in Hong Kong. Since its first issue in 1863, there has only been one period (1942–1947) where the coin was not in use. Before the Second World War the coin was first made of .800 purity silver, with a weight of 2.82 g, thickness of 1.1 mm and diameter of 17.50