What is "regent diamond"

Regent diamond \Re"gent di"a*mond\ A famous diamond of fine quality, which weighs about 137 carats and is among the state jewels of France. It is so called from the Duke of Orleans, Regent of France, to whom it was sold in 1717 by Pitt the English Governor of Madras (whence also called the Pitt diamond), who bought it of an Indian merchant in 1701.

The Regent Diamond is a diamond owned by the French state and on display in the Louvre. In 1698 a slave found the 410 carat (82 g) uncut diamond in Kollur mine (in Guntur District, Andhra Pradesh, India) and hid it inside a large wound in his leg. An English sea captain stole the diamond from the slave, killed him and sold it to an Indian merchant. Thomas Pitt, the Governor of Fort St. George, acquired it from a merchant in Madras in 1701, so it is sometimes also known as the Pitt Diamond. Thomas Pitt had the diamond cut in London, by the diamond cutter Harris, between 1704 and 1706. The cutting took two years and cost about £5,000

Pitt bought the diamond for £20,400 , and had it cut into a cushion brilliant. After many attempts to sell it to various Members of European royalty, including Louis XIV of France, it was purchased by the French Regent, Philippe II, Duke of Orléans, in 1717 for £135,000 , at the urging of his close friend and famed memoirist Louis de Rouvroy, duc de Saint-Simon. The stone was set into the crown of Louis XV for his coronation in 1722 and then into a new crown for the coronation of Louis XVI in 1775. It was also used to adorn a hat belonging to Marie Antoinette. In 1791, its appraised value was £480,000 .

In 1792, during the revolutionary furore in Paris, "Le Régent", or the regent diamond, was stolen along with other crown jewels of France, but was later recovered. It was found in some roof timbers in an attic in Paris. The diamond was used as security on several occasions by the Directoire and later the Consulat, before being permanently redeemed by Napoleon Bonaparte in 1801.

Napoleon used it for the pommel of his sword, designed by the goldsmiths Odiot, Boutet and Marie-Etienne Nitot. In 1812 it appeared on the Emperor's two-edged sword, which was a work of Nitot. Napoleon's second wife, Archduchess Marie Louise of Austria, carried the Régent back to Austria upon his exile. Later her father returned it to the French Crown Jewels. The diamond was mounted successively on the crowns of Louis XVIII, Charles X and Napoleon III.

Today, mounted in a Greek diadem designed for Empress Eugenie, it remains in the French Royal Treasury at the Louvre. It has been on display there since 1887. Experts have estimated the Regent Diamond value to be near £48,000,000. At the current 2015 exchange rate of $1.54 USD / £1, the Regent Diamond value is estimated at $73,920,000 USD.