James Avery 925 Sterling Silver Oval Amethyst Gemstone Ring Sz 5-5.25 $440 at JAJames Avery 925 Sterling Silver Oval Amethyst Gemstone Ring. For sale is a beautiful amethyst solitaire ring with a split shank, 4-prong basket design. The amethyst is a faceted oval cut measuring 11x9mm. The ring fits a size 5-5.25 and the.