The Spanish ollar (also known as the piece of eight, the real de a ocho, or the eight real coin) is a silver coin, worth eight reales, that was minted in the Spanish Empire after a Spanish currency reform in 1497. It was legal tender in the United States until an Act of the United States Congress discontinued the practice in 1857. Through widespread use in Europe, the Americas and the Far East, it became the first world currency by the late 18th century. Many existing currencies, such as the Canadian dollar, United States dollar and the Chinese yuan, as well as currencies in Latin America and the Philippine peso were initially based on the Spanish dollar and other 8 reales coins.