This is a lovely, foiled amethyst and rose cut diamond ring, circa 1750. One can still see vestiges of the red enamel that , when the ring was new, graced the basket back of the ring. In addition to the amethyst, the ring has four rose cut diamonds, with two on each shoulder. The ring is in amazing condition for it's 266 years. As always, the rings with basket backs can be difficult to size, because they show different sizes, depending on whether the front of the ring or the back is where one determines size, but I believe this one to be a size 7 and 1/2, by the way it fits on the sizer, and the way it fits my finger. It could be sized by one that is used to working with antiques, or with a sizing band. It is crafted of 18 carat gold (unmarked but tested), with the stones closed backed, and the diamonds set in silver. This is a lovely, feminine ring.; the amethyst measures 1/4 of an inch (maybe a little more) East to West, and it weighs 1.9 grams.