Suzanne Schiltz was hungry. Cleaning is exhausting business, especially as a hotel chambermaid in Paris — one of the most visited cities in the world, even in 1926. So when she saw an apple in the suitcase of two young men one December while neatening up their room, she took it. After a bite, Schiltz’ teeth struck something so hard they almost shattered: the Grand Condé diamond. It was one of the rarest gemstones in France. And it was also missing. Two months earlier, a couple of amateur thieves had robbed the historic castle, Château de Chantilly, 50 kilometres north of Paris. They had little more than a pair of tall ladders between them, but the extent of their burglary — more than 75 pieces of jewelry housed inside the castle’s museum, valued at $3,000,000 at the time — led the police to believe the culprits were seasoned acrobatic masterminds, or at least double-crossing museum staff. In fact, Leon Kauffer and Emile Souter were both demobilized French aviators in their early 20s, and well out of their depth. Despite their success in swiping the jewels, they failed to sell them. Before their arrest, Kauffer and Souter had only managed to make 30,000 francs (about $1,200 at the time) off the stolen loot. Their biggest mistake was stealing the Grand Condé, a 9.01-carat pink diamond so famous no jeweller would touch it for fear of incrimination. “Every policeman across Europe was looking for it,” said Mathieu Deldicque, chief heritage curator and director of the Musée Condé, in a phone call. This October, the naturally pink diamond will go on display at the Château de Chantilly to commemorate the 100th anniversary of the theft. It’s also the first time the piece has been shown at a major exhibition open to the public for a century, Deldicque said. The jewel has been in the Condé family’s possession since 1740. While its exact country of origin is still a mystery, with possible regions spanning from India to Borneo to Brazil, archival documents show it traveled to France where its first owner was Louis Henri de Bourbon, Prince of Condé — the prime minister between 1723 and 1726. The gemstone was originally set in a medal of the Order of the Golden Fleece — the most important order of knighthood — and was later removed to be mounted on a ring. A written proclamation from the 18th century commanded that every eldest Condé son must have their turn inheriting the diamond. “It was part of the symbolic heritage of this family,” Deldicque said. Although the curator declined to put a price on the diamond or its insurance cost, Deldicque did emphasize that “pink diamonds are the rarest and most expensive on the market.” In 1983, a similar sized gemstone was valued between US$500,000 and US$600,000, while in 2010, a much larger pink diamond sold for US$46 million. Neither have the historical provenance of the Condé diamond, however. Its theft is still front of Deldicque’s mind. Yes, it’s been 100 years. But it’s also been less than 12 months since another high-profile heist: the Louvre burglary in October 2025, where several priceless crown jewels were taken from the most famous museum in Paris. Many are still unrecovered. “Lots of historical diamonds were stolen,” he said of the Louvre theft. “We share great solidarity with our colleagues.” That incident almost made Deldicque change his mind on his own showcase, which had already been planned. “I hesitated for many weeks to postpone or to cancel the exhibition,” he said. But they persevered, and instead did something that likely protected the pink diamond from resale the first time around. With the support of L’École, School of Jewelry Arts, the museum was able to enlist gemologists from France, Canada and Switzerland to conduct extensive studies and scientific analysis on the stone’s chemical composition, rarity, clarity and density. They hope this bank of publicly available information detailing the jewel’s unique specificities makes it easily identifiable, and therefore, unsellable. Kind of like an “identity card,” Deldicque said. “You can’t do anything with it, because it’s too popular,” he said. While staging a public exhibition of such a rare piece is undoubtedly a risk, Deldicque insists it’s important to not be put off by the prospect of robbery — which seem to be mounting. Less than two weeks ago, a US$4 million diamond necklace once owned by Egyptian royalty was taken in a smash-and-grab robbery in Vienna, Austria. Beyond the Condé diamond’s historical significance, gemstones themselves “are works of art, and works of nature,” he said. “Diamonds are quite particular. You can’t enjoy them through pictures, videos, photographs and so on. Their color, their light, their presence are actually so strong that you have to see them in real life.” This pink diamond in particular, Deldicque says, even “has a bit of orange in it.”
