The Byzantine Empire considered itself a continuation of the Roman Empire, differing only that it was Christian and used Greek in speech. Most elements of Byzantine coinage came from the Romans, with the exception that they used Latin for the inscriptions. The Constantine coinage collapsed during the barbarian invasions in the early 5th century. By the time of Anastasius in 491, only the solidus, semissus (1/2 solidus) and tremissis (1/3 solidus), and a tiny copper coin called the nummus (1/7200 of solidus) had survived. In 498, Anastasius introduced a series of multiples of the nummus. The most important of these is the follis (worth 40 nummi). The follis was used extensively for the next 6 centuries and its creation is considered a good starting point for the history of Byzantine coinage. There are roughly 4 different periods of Byzantine coinage. The first runs from 491 through the mid 8th century. It is characterized by 3 denominations of gold coins (solidus, semissis, and tremissis), 5 denominations of copper (follis, half-follis, decanummium, pentanummium and nummus) and one of silver from 615 on (hexagram). The second runs from the 8th to the late 11th century. At this time the monetary system was simplified to one coin of each metal: the gold nomisma, the silver miliaresion, and the copper follis. The third covers the monetary reform of Alexius I in 1092 to about the end of the 13th century. There were several denominations of debased metal called trachea that were concave instead of being flat. A base (or unpure) gold coin called the hyperion replaced the nomisma, an even baser gold coin (electrum trachy) replaced the tremissis and trachea were created in base silver and eventually copper. There were also two denominations of small copper coins (tetarteron). The fourth covers the 14th century to the fall of the Empire in 1453 and saw the complete disappearance of gold coins and a return to the use of pure silver coins (basilicon, stavraton and hal
