Platinum and diamond brooch, circa 1930. The geometric plaque, centring a collet-set old European-cut diamond weighing approximately 1.00 carat, the pierced surround millegrain-set throughout with further diamonds together weighing approximately 3.00 carats, length 22 mm, width 49 mm, gross weight approximately 10.9 grams.. Condition: central diamond approximately G colour, Vs clarity