BITHYNIA. Nicomedia. Gordian III, 238-244. Tetrassarion (Bronze, 27 mm, 10.19 g, 6 h). Μ ΑΝΤ ΓΟΡΔΙΑΝΟC ΑΥΓ Radiate and cuirassed bust of Gordian III to right, cuirass decorated with gorgoneion. Rev. NIKOMHΔΕΩN ΔIC NΕΩKOPΩ King Nikomedes I standing front, head to right, sacrificing out of his left hand over altar, facing shepherd standing front, head to left, holding lagobolon in his right hand and raising his left; between them, erected serpent; above, eagle flying right, head left, and tetrastyle temple. RG 367. RPC VII.2 online ID 19965. Very rare. The obverse somewhat rough and with minor weakness on the reverse, otherwise, very fine.
The reverse of this highly interesting issue refers to the founding of Nicomedia by the Bithynian king Nikomedes I in 264/3 BC.