A stamp, created by a newspaper publisher when a British colony ran out of proper stamps in 1856, "will be by size and weight simply the most expensive object ever sold in history."  The British Guiana One-Cent Black on Magenta stamp will go up for auction at Sotheby's on June 17 and is expected to fetch between $10 million and $20 million. In the past, the most expensive stamp to ever sell at auction went for a far less-impressive-sounding $2.3 million.

This is what we know about the British Guiana:  A young stamp collector living in what is now Guyana found it among his late uncle's letters in 1873.  It was cut at the corners and a bit smudged, so Louis Vernon Vaughan sold it for six shillings, that as the same as about $1.50 at the time.  He sold it to a dealer.  By 1935 it had an estimated value of $40,000., but that dealer had already sold it.  The British Guiana hasn't been seen in public for 28 years and was last owned by convicted murderer John duPont, who died in prison four years ago.