Antoninianus Struck on a Denarius Flan?

442, Lot: 152. Estimate $200. Sold for $120. This amount does not include the buyer’s fee.

Gallienus. AD 253-268. Antoninianus (17mm, 2.54 g, 6h). Rome mint, 6th officina. 6th issue, AD 260-261. GALLIENVS AVG, radiate, helmeted, and cuirassed bust left, viewed from front, holding spear and shield; gorgon head on shield / VIRTVS AVG, Virtus standing left, holding shield on ground and vertical spear; VI in right field. MIR 36, 375aa; RIC V (sole reign) 325 var. (bust type); Cunetio –; Normanby –; Chalfont –. VF, green patina, smoothed and tooled. Extremely rare, only one noted by MIR (in a private collection).

Ex Münchener Numismatisches Antiquariat 7 (24 May 1989), lot 93 (incorrectly described as a denarius).

This coin has been struck on a very small flan, as has the coin illustrated as MIR 375aa. A third specimen (Lanz auction 121, 22 November 2004, lot 574) has an equally undersized flan. All three coins appear to be from the same die pairing, and the cause of this strange anomaly remains elusive. It is possible that flans had been prepared for striking denarii, but were used for antoniniani in error. Denarii with this reverse were indeed struck in the course of Issue 6, one specimen being recorded in MIR (421p).