Antique Engagement Ring Art Deco .79 Old European Cut Diamond in 18K White GoldThis Vintage, Art Deco Era engagement ring is practically a work of art. The center diamond is a . 79 carat old European cut diamond which is box set into an 18 karat white gold setting. The ring is slightly domed and is make up of dense filigree, milgrain detailing and negative space which extends down the shank. Measuring about 8mm wide, this ring really makes a statement.