Diocletian, AR quinarius, Rome. AD 291. 23 mm, 2.46 g. 

IMP DIOCLETIANVS AVG, laureate, draped and cuirassed bust right.
VIRTVS AVGG, Hercules, standing front, looking left, holding club and trophy.

No mintmark.

RIC V-2, 198 var. (rev. type) or 201 var (denomination).

With permission of Numismatica Ars Classica auction 120, Lot 830, Oct. 2020.