Sancy Hope diamond. The Sancy was in the collection of Vasiliy Rudanovsky until 1828 when purchased by Prince Demidoff for £80,000. It remained in the Demidov family collection until 1865 when sold to Sir Jamsetjee Jeejeebhoy, an Indian prince, for £100,000. He sold it only a year later, creating another gap in its history. It reappeared in 1867, displayed at the Paris Exposition, carrying a price tag of one million francs; the gem then vanished again for forty years. The Sancy next surfaced in 1906 when bought by William Waldorf Astor, 1st Viscount Astor, from famous Russian collector A.K.Rudanovsky. The prominent
English auction a Dutch auction would adjust the price in a direction that favored the bidders (lowering the price if the item is being sold to competing buyers, increasing it, if it is a reverse auction). When the auction involves a single item for sale and each participant has as an independent private value for the item auctioned, the expected payment and expected revenues of an English auction is theoretically equivalent to that of the Vickrey auction, and both mechanisms have weakly dominant strategies. Both the Vickrey and English auction, although very different procedurally, award the item to the bidder with the