Very rare, cuirassed bust right (lorica squamata) seen from the back, instead of from the front as usual. RIC online only cites two examples of this type, including this very coin, which illustrates the type!
Provenance: PAUL FRANCIS JACQUIER AUCTION 46 LOT 216 = ex. Philippe Gysen collection
OBVERSE: IMP C AVRELIANVS AVG
REVERSE: RESTITVTOR ORBIS
BUST TYPE: B4 = Radiate, cuirassed bust right, seen from back
FIELD / EXERGUE MARKS: -/-//*B
MINT: Cyzicus
ISSUE: 7.3 (autumn 272 – early 273)
WEIGHT: 2,90 g