Ross-Simons - C. 1990 Vintage 2.46ct Amethyst, .40ct t. w. Diamond Pendant Necklace. 18". C. 1990. Experience the allure of amethyst with this very classic pendant necklace from our Estate collection. Features a vivid 2.46 carat round amethyst haloed by .40 ct. t. w. round brilliant-cut diamonds. Finely crafted in polished 18kt white gold and suspended from a cable chain. Lobster clasp, diamond and amethyst pendant necklace. Exclusive, one-of-a-kind Estate Jewelry. Amethyst birthstones are the perfect gift for February birthdays.