Postumus AR Antoninianus. 259-268 AD. Lyons mint. 

IMP C POSTVMVS PF AVG, radiate, draped, cuirassed bust right
PAX AVGVSTI, Pax standing left, holding olive branch and sceptre. 

RIC V-II Lyons 79.

Contributed by Dane for Roma Numismatics, June 2009