How worn is the coin? Mint marks are often high points that get early wear.
Some of my coins were purchased 8-10 years or more ago, already in cardboard/mylar 2x2s for who knows how long, and they are in the same condition...
Perhaps "mislead" is too strong a word, but ""mistaken" certainly fits:
Depends on how long the print has been there. Relatively recent ones will disappear after a brief dip in pure acetone, such as you can obtain...
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