A star sapphire and diamond ring, circa 1950s,... Lot 137

A star sapphire and diamond ring, circa 1950s, featuring a cabochon sapphire displaying the optical effect of asterism with a six rayed star, measuring 16.6 x 16.2 x 7.6mm, with baguette cut and round brilliant cut diamonds set to each shoulder in a geometric design, the shank marked 'plat' and testing as platinum, ring size H, total weight 10.8 grams Provenance: from the family of Harvey Firestone, founder of the Firestone Tire and Rubber Company, one of the first global makers of automobile tyres; and thence by descent.