18ct Black Opal and diamond Ring R0012 $ 5,900.00 Australian superb gem grade black Opal from Lightning Ridge set in 18ct white gold with diamonds. Categories: Jewellery Rings Related collections Emerald cut diamond trilogy engagement ring $ 69,950.00 Two tone emerald cut diamond gents wedding band R0022 $ 5,916.00 Exotic Morganite and diamond ring in platinum R0014 $ 12,500.00 Black rhodium plating gents wedding band with white diamonds R0020 $ 6,750.00