The British Guiana One cent magenta dates to 1856 and was printed at a time of a postage stamp shortage. It measures just 29 by 26 millimetres, and was specially printed at a local newspaper office. It's the only surviving example of this short-lived stamp, and in the eyes of collectors, that means its original one cent value is now worth a staggering €12 million.
"The design of this stamp is pretty basic because it was printed under such rushed circumstances, and I think that adds to its appeal. They speak of history, not just postal history, but through their designs, history of nations. So, they encapsulate so much in so little, that's why they're attractive," said David Goldthorpe, Head of Books at Sotheby's auction house in London.
More than 150 years after it was made, this single stamp has been described as the most famous in the world. It's been sold at auction four times previously, each time setting a new record price for a single stamp. It most recently sold in 2014 when it raised nearly 8 million euros.
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