Two of the largest yellow diamonds ever offered for sale will be hitting the auction block in Geneva on Wednesday.
The pair of rocks, called the Donnersmarck Diamonds, total more than 185 carats and once belonged to French nobility.
They are part of the collection of La Paiva, a 19th-century French courtesan turned countess, who was well known for her vast collection of fine jewels.
"Count Guido [Henckel] von Donnersmarck bought these magnificent diamonds in 1882 for the love of his life, La Paiva," said Brett O'Connor of Sotheby's.
That royal provenance, plus their size and unique hue, has Sotheby's projecting the fancy intense yellow diamonds will fetch anywhere from $9 million to $14 million.
The jewels are some of the biggest and brightest in their classification, with the larger of the two weighing in at 102.54 carats and the smaller at 82.47 carats.
"They're extremely charming," said O'Connor. "And the love story connected with them is quite unique."
The stones will be showcased among various other gems of notable historic provenance at Sotheby's Magnificent Jewels and Noble Jewels sale in Geneva on Wednesday.
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Correction: An earlier version of the story incorrectly identified the century in which La Paiva lived.