Art Deco diamond cluster ring. Set with one central cushion shape old mine diamond in an open back millegrain collet setting with a weight of 1.20 carats, surrounded by two concentric rows of twenty eight round old cut diamonds in open back millegrain bead settings with a total weight of 2.80 carats. The approximate combined diamond weight is 4.00 carats, to an octagonal shape cluster above an ornate openwork arcaded gallery with pierced backholing and flanked by raised tri-part shoulders which flow through to a square shank. Tested platinum, circa 1935.