Æ25 - Valerian and Gallienus ΚΙΑΝΩΝ

Cius — the ancient harbor city on the Propontis later refounded as Prusias ad Mare — continued striking civic bronze well into the joint reign of Valerian and Gallienus, a period when the central imperial mint system was under severe stress from simultaneous barbarian incursions across the Danube and Persian campaigns in the east. Provincial cities in Bithynia maintained their own bronze coinage partly to fill the vacuum left by an increasingly debased and unreliable imperial silver supply.

The city's coinage effectively ceased after Gallienus ended most provincial bronze production empire-wide around 268 AD, making this among the final issues from Cius before that curtain fell permanently.