The Hope Spinel is expected to fetch up to AU$440,000 at Bonhams’ Fine Jewelry auction, which will be held on 24 September in London.
The 50.13-carat octagonal cut, rose-hued gemstone is set in a 19th century silver and gold brooch and surrounded by brilliant cut diamonds weighing approximately 6.5 carats. It was last offered for sale in 1917 where it sold for £1,060 – the equivalent of £80,000 (AU$174,294) today.
The piece was once part of a private collection of more than 700 gemstones formed by London banker Henry Philip Hope, who descended from a line of wealthy and powerful merchant bankers.
Before the unmarried Hope passed away in 1839, he secretly gave the collection to a nephew, an action that later caused a decade-long inheritance feud. The dispute also resulted in the separation of a number of items, including the Hope Spinel.
Emily Barber, director of Bonhams’ UK jewellery department, described the Hope collection as “one of the most important private collections of [gemstones] in the early 19th century”.
The assembly also included the famous Hope Diamond, which gained a reputation as being cursed after several owners experienced unfortunate circumstances such as execution and bankruptcy.
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TheHope Diamond is now housed in the National Museum of Natural History, part of the Smithsonian Institution in Washington DC in the US.
An ‘exceptional treasure’
Barber said the Hope Spinel was sourced from the ancient Kuh-i-Lal mines in Tajikistan, which were difficult to access geographically.
“We’ve had this spinel assessed by SSEF, a premier gemmological laboratory in Switzerland who have confirmed it is from these ancient mines, and due to its exceptional transparency, flawless cut, beautiful colour and large size, it’s classed as an exceptional treasure of nature,” she explained.
“Our estimate for the Hope Spinel is £150,000 (AU$326,505) to £200,000 (AU$435,470) but it could go for a lot more,” Barber added. “You just don’t see pieces of this quality and provenance on the open market very often. It’s very exciting.”
According to Bonhams, a spinel could sometimes be mistaken for a ruby as the two gemstones were found in the same rock formations, were chemically similar and often displayed a pinkish-red colouring.
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