Ancient Roman military ring with eagle. The central raised circular plaque engraved with the image of an eagle, flanked by broad trumpeting shoulders inscribed 'LEG(ion) / VIII', to a keeled tapering hoop. Tested silver, circa mid 3rd century AD.
The exalted Legio VIII Augusta was one of the oldest legions of the Imperial Roman army, serving for over 400 years. They were awarded the cognomen 'Augusta' for their assistance in gaining control of the Empire.
See Scarisbrick, D., 'Rings: Jewelry of Power, Love and Loyalty' p.23 for a comparable military ring.