Sotheby’s New York will offer the most famous stamp in the world in a dedicated auction on 17 June 2014. No stamp is rarer than the sole-surviving example of the British Guiana One-Cent Magenta, a unique yet unassuming penny issue from 1856, and no stamp is more valuable: each of the three times it has been sold at auction, it has established a new record price for a single stamp. The British Guiana is equally notable for its legacy, having been rediscovered by a 12-year-old Scottish boy living in South America in 1873, and from there passing through some of the most important stamp collections ever assembled. The stamp comes to auction this spring with a pre-sale estimate of $10/20 million*, which would mark a new world auction record for a stamp…
Wikipedia describes the rarity as follows:
The issue came about through mischance. An anticipated delivery of stamps by ship did not arrive so the local postmaster, E.T.E. Dalton, authorised printers Joseph Baum and William Dallas, who were the publishers of the Official Gazette newspaper in Georgetown, to print an emergency issue of three stamps. Dalton gave some specifications about the design, but the printer chose to add a ship image of their own design to stamps. Dalton was not pleased with the end result, and as a safeguard against forgery ordered that all correspondence bearing the stamps be autographed by a post office clerk. This particular stamp was initialled E.D.W. by the clerk E.D. Wight.
You can rest assured:
At one point, it was suggested that the 1c stamp was merely a “doctored” copy of the magenta 4c stamp of the 1856 series, a stamp very similar to the 1c stamp in appearance. These claims were disproven.