Diane Kordas 18-Karat Rose Gold Triple Cosmos Ring with Star Charm in Blue and White Diamonds. Diane Kordas' ring is part of the 'Cosmos' collection – each piece is defined by a charm that represents iconic symbols from classic geometry and history, to Pop Art. Cast from 18-karat rose gold, it's set with white diamonds and adorned with a signature dangling blue diamond star. The first row is plain, while the latter two are embellished with pavé-set white diamonds totalling 0.19ct. A blue-diamond pavé-embellished star charm, totalling 0.06ct, completes the design. We like how it creates the illusion of three slim bands stacked together.