Byzantine Ring with Inscription

5th-6th century AD. A bronze signet ring with large oval bezel, incised cross, a Greek inscription below '?? ? ?? C???????? ??, possibly a formula of invocation for Saint Stephan. See Wamser, L., Die Welt von Byzanz - Europas Östliches Erbe, München, 2004; Vikan, G., 'Early Christian and Byzantine Rings in the Zucker Family Collection' in, The Journal of the Walters Art Gallery, Vol. 45, (1987), pp.32-43. 8.51 grams, 26.58mm overall, 18.73mm internal diameter (approximate size British R, USA 8 1/2, Europe 18 3/4, Japan 18) (1"). Property of a London gentleman; from his private collection formed before 2000. [No Reserve]
Condition Report: Fine condition. A large wearable size.