A 400-year-old diamond known as the Beau Sancy is expected to sell for $4 million when it is auctioned off by Sotheby's in Geneva in May, the Associated Press reported.
The gem, which weighs 34.98 carats and is cut in a rare pear shape, is one of the oldest and most coveted diamonds currently under private ownership, the AP reported. It has been owned by the Royal Families of France, England, Prussia, and the House of Orange at different points throughout history, the Jewelry Editor reported.
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"It has a fascinating history, and really is a once-in-a-lifetime sale," David Bennett, Sotheby's jewelry chairman, told the AP. "When it was made in the 16th century, the pear cut was new, bold, and so it became the most sought-after jewel of its era. Before the 'Beau Sancy' all diamonds were rudimentary."
The diamond is currently on display in Paris, but will be also be shown in London, Zurich, Hong Kong, Rome, and New York before it is presented at an auction in Geneva on May 15, the International Business Times reported.
In 1604, King Henri IV of France purchased the Beau Sancy from its first owner, Lord of Sancy, for his wife, Marie de Medici, part of the famed Medici family of Italy, according to the IBT. When Henri died, the diamond changed hands from Medici to Frederick Henry, Prince of Orange, where it was passed down to Henry's descendants and to various royal families of Europe.
The jewel became one of the Prussian Empire's most prized stones, sitting in the royal crown and worn by female members of the royal Prussian family during important occasions, according to the IBT.
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The diamond originated in the Indian city of Golconda's renowned gem mines, and its 110 perfectly symmetrical faces were cut using a technique invented by Louis de Berquem, who is known as "the father of modern diamond cutting," according to the Daily Mail.
The Beau Sancy has only been shown publicly four times over the last 50 years, according to the Jewelry Editor: in Helsinki in 1972; in 1985 in Hamburg; in 2001 at the Musée National d'Histoire Naturelle in Paris; and in 2004, in Munich.