A wrong color on stamps can make them extremely valuable. The best known example is the “Tre skilling yellow” from Sweden (1855), which is one of the rarest stamps in the world. In 2010 it was sold for no less than 2,3 million $. You can read about this stamp in my blog at: stampstars.com. This week’s stamp is from the German state of Baden and shows the extremely rare color misprint of the 9 Kreuzer stamp issued in 1851. The stamps should have been pink but were mistakenly printed in green. In 2019, the stamp shown was sold for a record price of 1.26 million euros at the German auction: Heinrich Köhler.