Constantius II, Trier. 327-328 AD.

Obv: FL IVL CONSTANTIVS NOB C, Laureate and mantled 
bust left holding Victory on globe and mappa 
Rev: PROVIDENTIAE CAESS, Campgate with six layers, two 
turrets, star above 
Mintmark PTRE

Unrecorded in RIC or any of the major online databases. 
RIC 506 var (bust type). 

Contributed by the seller, rustyromans store on vcoins
August 2009.

RIC VII Trier 506 var (bust type)