Not quite up to the size and grandeur of the Smithsonian 400 pound Amethyst but with 15 carats of stunning pure purple Diamondeau? - flawless simulated?amethyst coming together in this luxurious designer setting this ring has maximum impact. At its heart is a beautiful 15ct cushion cut purple Diamondeau? -. Set on either side of this are single white Diamondeau? in a flower feature setting. A lavish layer of yellow gold has been added to sterling silver to give the look of rich solid gold. A real statement piece.