A nice piece with visible remnants of silver plating.
Obverse: head of Augustus in a pearl diadem, to the right, in the rim legend:
CONSTAN-TINVS AVG;
Reverse: camp gate of 6 rows of bricks, with open gate, in the rim legend:
PROVIDEN-TIAE AVGG; in SMNA section;
Bronze, diameter 19 mm, weight 2.76 g, axis 12 h.