Constantine II AE3. 

CONSTANTINVS IVN NOB C, laureate, cuirassed bust right 
CAESARVM NOSTRORVM around VOT dot X, palm branches to left and right. 

Mintmark: AQT. 

RIC VII Aquileia 115; Sear 17190.

With permission of Solidus Numismatik - Premium Auction 18, Lot 287, July 2017.