A Sotheby’s staff member shows a sparkling old mine-cut diamond brooch once owned by Emperor Napoleon I, crafted around 1810, during a preview event in Geneva, Switzerland, on Thursday, November 6, 2025. AP
Some of the world’s most dazzling diamonds — and a piece of history once owned by Napoleon Bonaparte — will go up for auction next week in Geneva. Collectors from around the world are expected to compete for these rare treasures, each with its own remarkable story.
At the centre of the event is a diamond brooch believed to have belonged to Napoleon himself. The piece, valued between US$150,000 and $250,000, will lead Sotheby’s annual Royal & Noble Jewels sale on November 12.
A jewel from Napoleon’s final days
The circular brooch, created around 1810, features a large 13.04-carat oval diamond surrounded by nearly 100 smaller old mine-cut diamonds. Measuring about 45 millimetres across, the jewel once symbolized the power and taste of the French emperor.
According to Sotheby’s, the brooch was among several personal belongings Napoleon carried with him to the Battle of Waterloo in 1815. As his army crumbled against British and Prussian forces, Napoleon fled in haste, leaving behind carriages filled with valuable possessions.
A few miles from the battlefield, one of those carriages became stuck in the mud. The Prussian army later discovered the contents, which included this brooch. On June 21, 1815—just three days after the battle—the jewel and other recovered items were presented to King Friedrich Wilhelm III of Prussia as trophies of war.
Pink diamond expected to draw huge bids
Alongside Napoleon’s brooch, another showstopper will dazzle bidders — a 10.08-carat vivid pink diamond named “The Glowing Rose.” Sotheby’s expects the gem to fetch around US$20 million.
Experts describe the diamond as “of exceptional quality,” noting its intensely luminous and pure pink colour, which is extremely rare in nature. The stone’s striking hue and clarity are expected to attract intense interest from collectors and investors alike.
Rival auction adds a blue diamond to the mix
The competition doesn’t stop there. Just a day before Sotheby’s event, Christie’s will auction a 9.51-carat vivid blue diamond, known as “The Mellon Blue.”
Set in a pendant, the gem once belonged to Rachel Lambert Mellon, better known as Bunny Mellon, a respected American philanthropist and art collector. The diamond, last seen at auction in 2014, sold for over US$32 million at that time. Experts now expect it could bring in as much as US$30 million this round.
Tobias Kormind, head of 77 Diamonds, said the stone might break the world record for price per carat for any blue diamond sold at auction. That record currently belongs to the Blue Moon of Josephine, which sold in 2015 for more than US$48 million, or US$4.1 million per carat.
A week of glamour and history
With treasures ranging from Napoleon’s lost jewels to some of the rarest diamonds ever found, next week’s Geneva auctions promise to be among the most exciting in years. For collectors, the events combine history, art, and luxury — all under one glittering roof.
