Ring with amethyst of approx. 10 ct flanked by chrome tourmaline cabochons,

Ring with antique faceted amethyste ca. 10 ct flanked by oval cabochon-cut chromtourmalines, beautiful colour, slightly abraded, 18K yellow gold, 16.6 g, ring size 55 (slightly visible changing of ring size), 20th/21st century, 20th/21st century, signs of wear, amethyste slightly loose, unknown maker's mark "SN".