1.20 Diamond Onyx Cocktail Ring 18k Yellow Gold. With bold lines and complementing colors, this Mid-Century cocktail ring features 1.20 carats of Round Brilliant cut diamonds finished in 18k yellow gold and onyx. A collection of forty (40) .03 carat diamonds are set in surface prongs in 18k yellow gold. Oval shapes and two sporty lines of yellow gold house the collection of diamonds on an onyx and yellow gold ring. The band measures 22.35mm wide. This ring is a fine example of Mid-Century jewelry design!