Constantius II AE3. Nicomedia. 326-327 AD.

Obv: FL IVL CONSTANTIVS NOB C, laureate, draped, cuirassed bust left
Rev: PROVIDEN-TIAE CAES dot, campgate, 7 layers, two 
turrets, no doors, star above. 

Mintmark NB
RIC VII, 147 (B = R2) Rare

Courtesy of deamoneta.com, 03. 2010