The follis was a type of coin in the Roman and Byzantine traditions.
A follis of Diocletian. 27 mm.
Caesar Constantius II on a follis AE3 of Heraclea of the year 325.
40 and 5 nummi of Anastasius.
Constantine VII and Zoe.
Byzantine currency, money used in the Eastern Roman Empire after the fall of the West, consisted of mainly two types of coins: gold solidi and hyperpyra and a variety of clearly valued bronze coins. By the 15th century, the currency was issued only in debased silver stavrata and minor copper coins with no gold issue.
Solidus minted during the second reign of Justinian II (705–711)
Anastasius 40 nummi (M) and 5 nummi (E)
Justinian I half-follis, 20 nummi. Note the K on the reverse.
Romanus III miliaresion.