Amethyst crystals grow in a twinning (parallel bands) hexagonal pattern. The color of the bands depends on availabilty of iron atoms. White means no iron was available as the atoms joined. The crystalline structure makes chevron in the banding. All that makes for a very distinctive gem. Bezel setting, with hammered texture frame.
GOLD - 14k yellow
GEMSTONE - Chevron Amethyst
CUT - Long pear-shaped cabochon, Round checkerboard-cut
CARAT - 131.88 ct, 8.68 ct.
SIZE - 24x57 mm, 13.5 mm
BAIL - Twin hidden bails 6x11mm inside
OA DIMENSIONS - length 78 mm