Koroosh & Valencia Original Design Platinum/18KY Blue Topaz Cocktail Ring with Diamond Accents. This Rectangle Checker-Cut Blue Topaz is accented by 18KY prongs and basket visible from the side making. Diamonds circle the center stone and side detailing, containing twenty round VS pave-set diamonds and a bezel-set diamond on each side of the center stone. The shank is full-round for your comfort.