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 coin type completes the Queen's Beasts series and combines all the Beasts in one image.
The Queen's Beasts are British coins issued by the Royal Mint in platinum, gold, and silver since 2016. Each of the coins in the series features a stylised version of one of the heraldic Queen's Beasts statues present at the coronation of Queen Elizabeth II, representing her royal line of ancestry. Engraver Jody Clark designed the entire series; he is best known for also designing the Queen's Fifth definitive portrait, which is on the obverse of the coins - so he is in the rare position of having designed both sides.
The Queen's Beasts heraldic statues representing the genealogy of Queen Elizabeth II stood in front of the temporary western annexe to Westminster Abbey for the Queen's coronation in 1953. Each of The Queen's Beasts consists of an heraldic beast supporting a shield bearing a badge or arms of a family associated with the ancestry of Queen Elizabeth II. They were commissioned by the British Ministry of Works from sculptor James Woodford. The statues were uncoloured except for their shields at the coronation. They are now on display in the Canadian Museum of History. There are other statues of the Queen's Beasts, sometimes referred to as the King's Beasts, at Hampton Court Palace and Kew Gardens in London, and on the roof of St George's Chapel, Windsor Castle.
The Royal Mint says:
"For the series finale, Jody was set the formidable challenge of capturing all ten beasts side by side in a single design. The result is a remarkable feat of miniaturisation, testament to his deft touch and the skills he has honed working in this format. The visual impact is both impressive and immediate. Presented together on one coin, these magnificent royal guardians - lions, a griffin, a falcon, a bull, a yale, a greyhound, a dragon, a unicorn and a horse - exude the power and symbolism associated with the British monarch." | 
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