Watch List notes:

Diadumenian. As Caesar, A.D. 217-218. AR denarius (20 mm, 2.78 g, 7 h). Rome mint. M OPEL ANT DIADVMENIAN CAES, bare-headed and draped bust right / PRINC IVVENTVTIS, Diadumenian standing left, head right, holding scepter and standard; two additional standards to his right. RIC 102; BMC 87-91; RSC 3. Fine, toned, flan crack. 

Ex Superior (11-16 December 1972), 570.