Known as the world’s most valuable and rare stamp, this unique piece was produced during a stamp shortage in British Guiana. Only one copy is known to exist, discovered by a 12-year-old Scottish ...

These are the most valuable stamps from around the world ... One hundred forty years later, the British Guiana 1 Cent Magenta sold for over 6.4 million times that amount and reached $9.48 million ...

Most collectors are happy to pursue ... was titled “Three Treasures” and the third was the British Guiana One-Cent Black on Magenta stamp from 1856. Despite it carrying a $10m lower estimate ...