Rare follis.
R1 in the Roman Imperial Coinage catalogue.
Roman Imperial
Constantine II (337–340) - as Caesar 317–337, Follis 325-326, Heraclea mint
Obverse: laureate, draped and cuirassed bust right
CONSTANTINVS IVN NOB C
Reverse: camp gate with two turrets, without doors, star above, SMHA in exergue
PROVIDENTIAE CAESS
Diameter 20 mm, weight 2.81 g