City Commemorative, AE4, Rome mint, 337-340 AD.

CONSTANTINOPOLIS (no legend break), helmeted bust of
Constantinopolis left, wearing necklace and ornamental 
mantle, sceptre over left shoulder.
No legend, Victory standing facing on prow, head left,
holding sceptre, and resting hand on shield.

Mintmark R leaf epsilon. 

RIC VIII Rome 18; Sear -. 

Image courtesy of Uni Freiburg, inv. 7352.