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 £20 coin celebrates the Platinum Wedding (or 70th anniversary of the marriage) of Queen Elizabeth II to Prince Philip, Duke of Edinburgh.
The reverse was designed by John Bergdahl, and the obverse by Etienne Millner. The Royal Mint says about the design:
"A platinum wedding anniversary is a significant event for any couple. For two people who have lived their lives under the glare of public and media scrutiny, it is a testament to their unwavering devotion, strength of character and good humour.
Two sides of this world-famous yet down-to-earth couple are brought to life on this coin. Etienne Millner’s combined portrait on the obverse represents a sense of duty, His Royal Highness The Prince Philip, Duke of Edinburgh supporting Her Majesty The Queen in his role of royal consort. On the reverse, John Bergdahl’s equestrian portrait captures the couple sharing their love of horses side-by-side." | 
Search for United Kingdom: Twenty Pounds 2017 Platinum Wedding on eBay 
