Watch List notes:

Helena (Constantine I, 307-337), Nummus, Siscia, AD 328-329; AE (g 2,82; mm 19; h 6); FL HELENA - AVGVSTA, diademed and draped bust r., Rv. SECVRITAS - REI PVBLICE, Securitas standing l., holding branch and raising skirt; in ex. εSIS double crescent. RIC 218.
Green patina, high relief, extremely fine.