Cartier Emerald and Diamond Cocktail Ring in Platinum.  This beautiful Cartier cocktail ring features a pear cut emerald and diamond encircling each other in a toi et moi fashion. The ring is set in platinum and is accented by twelve (12) baguette diamonds that lead along the shoulders to the two pear cuts. This ring is complete with a Finger Mate expandable shank, which is perfect for getting over large knuckles and then returning to the size of your finger.