An Art Deco sapphire and diamond brooch, circa 1920

An Art Deco sapphire and diamond brooch, circa 1920, centring on an oval cabochon sapphire weighing approximately 10.00 carats, to a geometric bar brooch channel-set with calibré-cut sapphires, and outlined with single-cut diamonds in millegrained borders, mounted in platinum, length 6.6cm, French assay marks for platinum, French maker's mark GT with arrow

Accompanied by AGL report no.1109360, Dated August 28th 2020, Stating that the oval cabochon sapphire measuring 15.5x11.4x6.05mm is of Sri Lankan (Ceylon) origin with no indication of heat treatment.