BITHYNIA. Prusa ad Olympum. Diadumenian, as Caesar, 217-218. Diassarion (Orichalcum, 25 mm, 5.90 g, 6 h). M OΠЄΛ ANTΩNINOC ΔIAΔOYMЄNIANOC Bare head of Diadumenian to right. Rev. ΠPOYCAЄΩN Ajax, wearing helmet and balteus, falling on his sword before a rocky outcropping; shield on ground before him. RG 123. SNG Copenhagen -. SNG von Aulock -. Very rare. Spots of corrosion and with some deposits, otherwise, fine.