A sapphire single-stone ring, circa 1950. Photo: Bonhams. The large step-cut sapphire, weighing 23.24 carats, between shoulders set with baguette and brilliant-cut diamonds, ring size O½, cased by Collingwood of Conduit St, 46 Conduit St, W1. Estimate...

A fine sapphire single-stone ring. Photo courtesy Bonhams. The octagonal sapphire, weighing 11.85 carats, between square-cut diamond shoulders, the gallery and shoulders decorated with single-cut diamonds, ring size K. Estimate £80,000 - 120,000 (97,000...