As it is so unusual it has meant the coin has been dubbed the "holy grail" of change collecting making it much sought after. The 20p coin was highlighted on Instagram by Coin Collecting Wizard.

A rare minting error on a small number of 2008 twenty pence coins has made them highly desirable among collectors, with some expected to sell for as much as £100 at ...

A rare minting error on a small number of 2008 twenty pence coins has made them highly desirable among collectors, with some expected to sell for as much as £100 at ...

An unusual coin could net its owner over 250 times its face value after an error when it was made. The rare 20p coin was one of an unknown number released by the ...

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