An Art Deco sapphire and diamond necklace

An Art Deco sapphire and diamond necklace, circa 1935. The centre slightly oval shaped sapphire weighs approximately 5.45cts and is set within a shield shaped plaque which is set with graduated circular and baguette shaped diamonds. The graduated sides are set with further sapphires and diamonds with a single row box set circular cut diamond back section. French control mark to tongue. 37cm.