Valerian, AE23 of Nicomedia, Bithynia. 253-260 AD. 7.53g.

PO LIK OVALERIANOC AVG, radiate, cuirassed bust right.
NIKOMHDEWN DIC NEWKORWN, Valerian on horseback 
galloping right, holding spear, "FI" countermark (not in
Howgego for this time period).

RecGen 404; BMC 67; 
Rare. 

With permission of Romae Aeternae Numismatics, May 2013.