Aquamarine and diamond brooch, circa 1920, centring an emerald-cut aquamarine weighing approximately 5.00 carats bordered by baguette diamonds flanked by an open work geometric motif millegrain-set throughout with circular-cut diamonds, the diamonds together weighing approximately 1.86 carats, mounted in platinum, approximately 40 x 15 mm. Accompanied by a Mappin & Webb fitted case.