Art Deco Sapphire & Diamond Engagement Ring in PlatinumArt Deco Sapphire Diamond Engagement Ring in Platinum. This Art Deco engagement ring features a 1. 54 carat round cut sapphire and . 04 carats of small accent diamonds set in platinum. The setting is a beautiful lattice of ornamental wire work full of twirling open spaces across a domed side profile. The sapphire is set with fishtail prongs with a thin line of accent diamonds running down the shoulders. This lovely piece of Art Deco style is a