Some of the world’s most valuable stamps include the British Guiana 1c Magenta, which most recently sold for $8.31 million, and the Treskilling Yellow, a rare misprint from Sweden.
It may sound a lot for "a small patch of paper", said The Guardian, but it's far from being the most expensive old stamp ever sold. In 2021, an envelope featuring a Mauritius Post Office 1d red ...