Interesting double struck of the reverse.
Coin from the collection of prof. Bartosz Awianowicz.
Byzantine Empire
Phocas (602-610), Follis, Constantinople mint
Obverse: crowned bust facing, holding mappa and cross
d m FOCAS PERP AVG
Reverse: large XXXX, ANNO above, CON in exergue
Diameter 34 mm, weight 10.42 g