One of the most famous and expensive stamps of German Post is the Baden 9 Kreuzer issued in 1851. This stamp was issued by the historical State of Baden in Germany. This is an error stamp that is known worldwide because only four copies of this type are known.
The stamp was the first issue of the Baden Post. A colour misprint makes this a much sought after stamp. The original colour chosen for this stamp was pink, instead, it came up with green, which was intended for 6 Kreuzer value. This stamp is one of the greatest philatelic rarities. The three out of four stamps depict a cancellation mark, but only one of them was unused.
This Baden 9 Kreuzer stamp was sold for 1,545,000 US dollars.
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