Silver antoninianus, 23mm, 2.73gm, issued AD 257/258. Cologne mint.
Obv: VALERIANVS CAES, Radiate, draped bust facing right.
Rev: IOVI CRESCENTI, Infant Jupiter riding Amalthaean goat right.
A similiar reverse was used by Vespasian on Domitian's coinage - presumably the type indicates the young Caesar hopeful ascendency to Emperor, just as Jupiter grew to become King of the Gods. The young Valerian II died, however, soon after taking command in Illyria..