Through an Israeli blog on stamps I came across this fascinating story about a stamp that was issued in Communist China on November 1968 called “The entire nation is red”. Have a close look :

There’s an interesting story behind this (source) :
The stamp was quickly withdrawn from circulation because Taiwan, which is claimed by the People’s Republic of China, was colored white instead of red, which contradicted the motto on the stamp, "The Entire Nation is Red." The official explanation is that "An editor from China Atlas Press found out that the map on the stamps was inaccurate because the Xisha and Nansha archipelagos were absent." The sale of the stamp was stopped after less than a day. It was not reissued.
In case you’re wondering, this stamp is extremely rare and is now valued by collectors to be worth tens of thousands of US dollars.
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