PRL, 10 zlotych 1965, Nicolaus Copernicus, SPIRIT

The reverse shows the so-called "ghost" in the form of a clear reflection of the eagle's wings and the number 9 in the field, next to the figure of Copernicus. Mint defect created when the stamps come into contact without the coin disc between them, then the stamps hit each other, transferring fragments of the design onto each other.