31 CT AMETHYST AND DIAMOND NECKLACE: 54 Amethysts approx 31.14 CTW and 77 round diamonds approx 2.47 CTW form this unique necklace. The amethyst is an intense violet-purple and the diamonds are SI2-SI1 in clarity, H-I in color. 16'' long. 23.9 grams. Sold with Gemological Laboratory Services appraisal for $14,875 dated December 15, 2017.