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
Guinea (coin) Guinea (coin) The guinea was a coin of approximately one quarter ounce of gold that was minted in Great Britain between 1663 and 1814. The name came from the Guinea region in West Africa, where much of the gold used to make the coins originated. It was the first English machine-struck gold coin, originally worth one pound sterling, equal to twenty shillings, but rises in the price of gold relative to silver caused the value of the guinea to increase, at times to as high as thirty shillings. From 1717 to 1816, its value was officially fixed at twenty-one shillings.