I Found this coin among my dad's collection, in a 2x2 folder labeled Constantine. When I try to research that name, about a zillion combinations appear, and none matching the exact obverse/reverse combination. Can anyone help identify this ?
Your coin is not of Constantine, but rather of the Roman emperor Gratian (367-383 AD). The inscription on obverse reads DN GRATIANVS PF AVG (Dominus Noster Gratianus Pius Felix Augustus) [Our Master Gratian, Pious, Blessed, Augustus). If you post this in the "Ancients" section, others can give you more info.
It is Gratian, to begin with. The legend says: DN GRATIA-NVS PF AVG I will look to see if I can find it now.