The coins have been dubbed the 'holy grail' of change collecting and if you find one it could be worth a lot more than 20p ...

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 Royal Mint without a date.

the 20p coin sold for £90. The rarest is the Kew’s Garden 50p, which was designed to mark the 250th anniversary of the ...

the 20p coin sold for £90. The rarest is the Kew’s Garden 50p, which was designed to mark the 250th anniversary of the gardens in 2009. Only 210,000 coins were ever minted with this design.

Around 250,000 20p coins minted in November 2008 are believed ... Only 210,000 coins were ever minted with this design. The Kew Gardens 50p sells for £156.25 on average, but one seller received ...

Around 250,000 20p coins minted in November 2008 are believed to have entered ... Only 210,000 coins were ever minted with this design. The Kew Gardens 50p sells for £156.25 on average, but one seller ...