Diadumenian. Silver Denarius (3.45 g), as Caesar, AD 217-218. Rome, under Macrinus, AD 217. M OPEL ANT DIADVMENIAN CAES, bare-headed and draped bust of Diadumenian right. Reverse: PRINC IVVENTVTIS, Diadumenian, in military attire, standing left, head right, holding standard and scepter; behind him, two standards. RIC 102; BMC 87-91; RSC 3. Luster present and lightly toned. NGC photo cert grade Ch AU; Strike: 3/5, Surface: 5/5. Estimated Value $500 - UP 

This denarius was struck in Rome soon after Diadumenian's elevation to the rank of Caesar, perhaps in celebration of his ninth birthday in September, AD 217. The reverse depicts Diadumenian standing amid Roman military standards in his role as 'Prince of Youth,' a title traditionally given to the heir to the imperial throne.
Ex The William Oldknow Collection.