At the time of decimalisation in 1971, the United Kingdom Crown coin (equal to 5 shillings) was redenominated as a 25p coin and pieces struck prior to 1990 - all the way back to 1818 - continue to be legal tender for that amount. The old denomination had been a regular circulating coin in the 19th century, but in the 20th century it became more of a commemorative denomination.
The Royal Mint continued issuing commemorative coins in the same format - using the traditional coin dimensions, but in copper-nickel. These were initially also denominated as 25 pence but the "Crown" was changed in 1990 to a commemorative £5 (five pound) coin, having the same dimensions and weight but with a face value twenty times as great.
The denomination is used to mark special occasions, usually royal in theme, rather than for use in general circulation. Although not circulating, these coins are legal tender.
This £5 Crown-sized commemorative coin is part of a large series of coins issued by the Royal Mint commemorating the First World War.
It is dedicated to Remembrance Day - an annual day of reflection where our collective thoughts turn to those who sacrificed so much to ensure the freedom of future generations. In addition to the typical Armistice tributes, 2020 also marks a very special anniversary - the historic centenary of the burial of the Unknown Warrior.
As the Royal Mint explains:
"In 1920, the decision was made to honour all those who died during the First World War with the ceremonial burial of an anonymous fallen hero. The unnamed soldier would symbolise all those who had made the journey to the front lines and never returned home. As we mark the 100th anniversary of this poignant national event, The Royal Mint commemorates this momentous occasion by honouring the Unknown Warrior on an official UK coin for the first time. Find out more about the coin’s design and the fascinating story that inspired it." | 
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