The Grand Sapphire of Louis XIV
E.W. Streeter, in his book Precious Stones and Gems (1892), describes a number of fine sapphires. One of these was in the collection of the Musée au Jardin des Plantes, in Paris, and weighed 133.06 carats. The same stone was also described by Sourindro Mohun Tagore in his classic, Mani-Málá (1879, 1881), referring to it as the Wooden Spoon-Seller’s Sapphire, in reference to the poor man who is said to have found it in Bengal, India. Streeter said it was without flaw. This is undoubtedly the same stone that resides today in Paris's Museum of Natural History, for it is of a distinctive lozenge shape and possesses only six facets, appearing like a huge sapphire rhomb. It is indeed nearly "without flaw," containing only one small feather and crystal inclusion, and is possibly of Burmese or Sri Lankan origin.
According to the museum's H.J. Schubnel, the sapphire actually weighs 135.80 carats. In the museum it is known as the Ruspoli Sapphire. During the 17th century, a Roman prince named Ruspoli sold this sapphire to a salesman, who in turn, sold it to King Louis XIV sometime before 1691. At that time it was the third most prominent gem in the French Crown Jewels.
During the French Revolution, the royal gems were confiscated by the revolutionary government and then stolen by Cadet Guyot. Only a few escaped, including the Ruspoli Sapphire, probably saved by its unusual form. In 1796, the revolutionary government allowed the Museum to choose a few gems for educational purposes. Daubenton, the Museum’s director, chose the Ruspoli Sapphire, cleverly labeling it as a sapphire crystal. Obviously he was lying, but it was for a noble cause. Today the Ruspoli Sapphire can be viewed in the Paris Museum of Natural History.
In 2016 the Gemological Institute of America published an article their "Gems & Gemology" periodical stating that the name 'Ruspoli Sapphire' actually applied to a separate, cushion-shaped sapphire: The Grand Sapphire of Louis XIV and The Ruspoli Sapphire