The positions of the K-absorption edges of iron are recorded for five crystals: FeO, FeO, FeO, FeO and Fe metal, and for two amorphous solids: oxide glass ([NaO · 2SiO] [FeO]) and metallic glass (FeCrNiPB). It is observed that there is a correlation between the positive X-ray K- absorption edge chemical shift and the effective coordination charge. The ionic state of iron in oxide glass is identical to the ferric iron in FeO as shown by the same positions of iron K-absorption edges in this glass and FeO. The K-edge of the metallic glass appears 6.5 eV higher than that of the pure iron edge, which suggests that the bonding of iron in metallic glass is different from the pure iron metal. © 1980.