Carly's Black 3 Carat Oval CZ Engagement Ring Get bold beauty with Simulated Black Diamond Engagement Ring - 3 Carat Oval CZ. Features a .925 sterling silver, rhodium plated design. Black oval cut CZ center stone measures 3 carats. Accent stones surround center stone forming a halo effect. Split band on each side is encrusted with round cut CZ stones. Get bold with this black beauty. It's unique and perfect for any look!