Diadumenian AE As, 217-218 AD, Rome. 13.65 g. 

M OPEL DIADVMENIANVS CAES, bare-headed, draped bust right. 
PRINC IVVENTVTIS, SC in ex. Diadumenian in military
dress, standing left, holding rod and sceptre; legionary
eagle and standard behind him.

RIC 216; Cohen 13

With permission of Helios Auction 5, June 2010, lot 347
Added in Aug. 2011.