The Twenty Pounds (£20) is a non-circulating legal tender (NCLT) coin issued by the Royal Mint since 2013.
The denomination is used to mark special occasions, usually royal in theme, and is not intended for general circulation - which is served by a banknote of the same value instead. The coins are legal tender, but contrary to popular belief this does not mean that banks and retailers automatically have to accept them (in practice, they do not accept them).
This commemorative £20 silver brilliant uncirculated coin celebrates the 90th birthday of Queen Elizabeth II.
The Royal Mint says about the coin:
"Her Majesty The Queen has celebrated many landmark moments during her long and eventful reign birthdays, jubilees and wedding anniversaries and we have enjoyed each happy occasion with her. Now we celebrate with the Royal Family once again as Queen Elizabeth II becomes the first British monarch to reach a 90th birthday. As this much loved public figure reaches another remarkable milestone, at The Royal Mint we are delighted to release a commemorative coin for the occasion. To wish Her Majesty every happiness as royal history is made, acclaimed artist Christopher Hobbs has turned to her love of flowers for inspiration, his design approved by The Queen herself. As this is a more personal occasion, the artist has filled the classical wreath with natural rather than heraldic roses, with each one different to the next." | 
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