Watch List notes:

Diadumenian, as Caesar, As, Rome, AD 217; AE (g 10,51; mm 26; h 6); M OPEL ANTONINVS DIADVMENIANVS CAES, bust draped and cuirassed, Rv. PRINC IVVENTVTIS, Diadumenian standing l., head r., holding sceptre and standard; on r., two standards; in ex. S C. RIC 212; C 8.
Rare, brownish patina, about extremely fine.