.75 Diamond & Cushion Cut Sapphire Engagement Ring in PlatinumDiamond Cushion Cut Sapphire Engagement Ring in Platinum. This ring from the Art Deco period is simply stunning with its . 75 carat Old European cut diamond and two (2) . 62 carat cushion cut sapphires. The ring is finished in 18 karat white gold and is a spectacular example of the opulent style of the 1920s. Sitting high above the finger with wonderful filigree work and small accent diamonds to create even more sparkle, this ring has a bright spark