Gallienus, AE antoninianus, Lyons, joint reign. 259 AD.

GALLIENVS PF AVG, radiate, cuirassed bust right.
SPQR OPTIMO PRINCIPI in four lines within laurel wreath.

RIC V-I, Lyons 37, rated scarce. 

Note RIC V-I, Lyons 37 (joint reign has no exergual line);
RIC V-I Asian Mint 659 DOES have an exergual line (but no 
mintmark or officina letter either).

With permission of cngcoins.com. Sold for $250.