Size Medium Silver. Womens size 7 REGAL ROSE BITTERSWEET. Double Serpent Onyx Ring - Silver Large square Onyx gemstone set within a claw pronged Cathedral setting. Featuring a deadly double headed Serpent ring band. The double headed serpent known as 'Amphisbaena' is a mythological ant-eating creature spawned from the blood that dripped from Medusa’s head. 925 Sterling Silver Band width 2mm Ring depth 10mm Gemstone measures 10mm Allergen Safe - AnchorCert Protected