Diocletian, AE As, 22mm. 5.41 gr. 285-286 AD. 

IMP DIOCLETIANVS AVG, laureate, draped, cuirassed bust right.
IOVI CONSERVAT AVG, Jupiter, naked except for chlamys over
shoulders, standing left, holding thunderbolt and sceptre.

RIC V 191 var (denomination, rev. legend). 

Very rare.

Contributed by Dr. Hubert Lanz, auction November 2000, 
Added July 2011.