The ducat (ˈdʌkət) coin was used as a trade coin in Europe from the later Middle Ages from the 13th to 19th centuries. Its most familiar version, the gold ducat or sequin containing around of 98.6% fine gold, originated in Venice in 1284 and gained wide international acceptance over the centuries. Similarly named silver ducatons also existed. The gold ducat circulated along with the Florentine florin and preceded the modern British pound sterling and the United States dollar. The word ducat is from Medieval Latin ducalis = "relating to a duke (or dukedom)", and initially meant "duke's coin" or a "duchy's coin". The first issue of scyphate billon coins modelled on Byzantine trachea was made by King Roger II of Sicily as part of the Assizes of Ariano (1140). It was to be a valid issue for the whole kingdom. The first issue bears the figure of Christ and the Latin inscription Sit tibi, Christe, datus, quem tu regis iste ducatus (meaning "O Christ, let this duchy, which you rule, be dedicated to you") on the obverse. On the reverse, Roger II is depicted in the style of a Byzantine emperor and his eldest son, Duke Roger III of Apulia, is depicted in battle dress. The coin took its common name from the Duchy of Apulia, which the younger Roger had been given by his father. Doge Enrico Dandolo of Venice introduced a silver ducat which was related to the ducats of Roger II. Later gold ducats of Venice, however, became so important that the name ducat was associated exclusively with them and the silver coins came to be called grossi. In the 13th century, the Venetians imported goods from the East and sold them at a profit north of the Alps. They paid for these goods with Byzantine gold , but when the Byzantine emperor Michael VIII Palaiologos backed the revolt of the Sicilian Vespers in 1282, he debased the . This was just one more in a series of debasements of the , and the Great Council of Venice responded with its own coin of pure gold in 1284. In 1252 Florence and Genoa introduced the gold florin and genovino, respectively, both of 3.