Byzantine Coins - Giambonino Collection

Constans II - 641-688 AD
Constantinople mint.
According to the British Museum, Department of Coins and Medals, Duty Curator, this coin "appears to be of Constans II" and this is the description:
Obverse: right bust of Constans II
Reverse: large M, surmounted by the bust of Constantine IV; to the left and right, busts of Heraclius and Tiberius.
These coins were often over struck.