Antoninianus - Diocletianus MARS VICTOR or MARS NICTOR; Mars

Diocletian's earliest antoniniani, struck before the Coinage Reform of 294 AD, represent the final gasp of a denomination that had been debased from near-pure silver to a bronze core with a thin silver wash over the course of half a century. The RIC V.2 #239 type belongs to this pre-reform phase, when Diocletian was still working within the inherited monetary chaos of the third century rather than dismantling it. His systematic reform — introducing the argenteus and the nummus — would effectively retire the antoninianus entirely.

The "NICTOR" legend variant, a known engraver's error for "VICTOR," appears sporadically across this type and is well documented rather than a die slip unique to individual specimens.