Helena, mother of Constantine, AE Follis, struck AD 327-328 at Nikomedia mint. Obv: FL HELENA AVGVSTA, diademed and draped bust right. Rev: SECVRITAS REIPVBLICE / SMHE (in exergue), Securitas standing left, lowering branch with left hand, raising robe with right hand. 2,44 g, 18 mm. RIC 218