Ancient Roman Silver Ring with an important Early Type of an Important Christian Symbol Ж Chi-Rho (Christogram). Significant Early Christian Symbol. ☧ Chi-Rho symbol was used by the Roman Emperor Constantine the Great (r. 306–337 AD) as part of a military standard (vexillum). Constantine had dreamt of being ordered to put a "heavenly divine symbol" on the shields of his soldiers. Emperor Constantine ordered to be inscribed on the next morning, as reported by Lactantius. That very day Constantine's army fought the forces of Maxentius and won the Battle of the Milvian Bridge (312), outside Rome.Intact and still Wearable with a lovely brownish patina. Very Rare. inner diameter: 18 mm. outer diameter: 21 mm. weight: 2.04 g.