A 17.43-carat Kashmir sapphire ring sold for £723,062 ($945,000), a price that equates to $53,956 per carat, at Bonhams London Jewels sale on April 30.
Dating from the late 19th to early 20th century, the cushion-shaped sapphire was formerly owned by a European noble family. It was the first time it had appeared at auction, attracting interest from multiple bidders, before it eventually sold to a telephone buyer, far exceeding its pre-sale estimate of £300,000-£400,000 ($392,000-$523,000).
The second highest performing lot was a diamond and sapphire transformable necklace by Spanish jeweller Grassy. Dated circa 1935 and featuring a 34.59-carat Sri Lankan unheated sapphire, the necklace sold for £287,562 ($376,000) against its pre-sale estimate of £120,000-£180,000 ($157,000-$235,000).
Other sales included a 9.07-carat step-cut diamond ring of F colour, Type IIa and potential VVS1 clarity, that went for £250,062 ($327,000).
Also sold was an emerald and diamond 'Two Bees' ring by Jean Schlumberger for Tiffany & Co., dating from the mid 20th century. The ring features a 22.02-carat step-cut Colombian emerald sitting within an elaborate mount formed of two marquise and brilliant-cut diamond honey bees and two curving brilliant-cut diamond leaves, which sold for £100,062 ($131,000) against its pre-sale estimate of £65,000-£85,000 ($85,000-$111,000). The ring was in the collection of Andy Warhol, who was an avid — yet secretive — collector of jewellery.