Hello friends,
I believe this coin is from Antioch which didn't mint this type for Constantius II. Instead, I believe this is actually Valens.
RIC IX Antioch 12b. (Officina 1 or 4)
O:DN VALENS-PF AVG, pearl-diademed, draped, cuirassed bust right
R:SECVRITAS-REIPVBLICAE, Victory advancing left, holding
wreath and palm branch. ANT[A or delta] in exergue
Cheers,
-Kurt

I believe this coin is from Antioch which didn't mint this type for Constantius II. Instead, I believe this is actually Valens.
RIC IX Antioch 12b. (Officina 1 or 4)
O:DN VALENS-PF AVG, pearl-diademed, draped, cuirassed bust right
R:SECVRITAS-REIPVBLICAE, Victory advancing left, holding
wreath and palm branch. ANT[A or delta] in exergue
Cheers,
-Kurt























