Given him by his sister Canacë. It had the virtue of healing wounds. (See Cambel .) (Spenser: Faërie Queene, bk. iv.)
Spenser: Faërie Queene, iv. 3.Well mote ye wonder how that noble knight, After he had so often wounded been, Could stand on foot now to renew the fight ... All was through virtue of the ring he wore: The which, not only did not from him let One drop of blood to fall, but did restore His weakened powers, and dulled spirits whet.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894