The miliaresion, is a name used for two types of Byzantine silver coins. In its most usual sense, it refers to the themed flat silver coin struck between the 8th and 11th Century.
Example of the first miliaresia, struck by Leo III (r. 717–741) to celebrate the coronation of his son, Constantine V (r. 741–775), as co-emperor. Notice the lack of any imagery except the cross.
A rare example of a hexagram of Theodosius III (r. 715–717), struck just a few years prior to the introduction of the miliaresion. Note the design of the hexagram's cross which was carried through when designing the miliaresion's obverse.
Leo III the Isaurian, also known as the Syrian, was Byzantine Emperor from 717 until his death in 741 and founder of the Isaurian dynasty. He put an end to the Twenty Years' Anarchy, a period of great instability in the Byzantine Empire between 695 and 717, along with bringing an end to the continual defeats and territorial losses the Byzantines had suffered during the seventh century, marked by the rapid succession of several emperors to the throne. He also successfully defended the Empire against the invading Umayyads and forbade the veneration of icons.
Example of the miliaresion silver coins, first struck by Leo III to commemorate the coronation of his son, Constantine V in 720.