Constantine I  AD 306-337 AE3, Nicomedia mint, struck 328-329 AD. 

CONSTANTINVS AVG, head right wearing triple-rowed pearl diadem. 
PROVIDENTIAE AVGG, campgate with seven rows, 

Mintmark SMNB. 

RIC VII Nicomedia 153; Sear 16260.

With permission of Eidmar auction 5, (on biddr.com), Nov. 2024.