Like many other mints, the Royal Mint issues bullion coins in precious metals, having much higher intrinsic value than their face value. The half ounce (1/2 oz) gold coins are denominated as Fifty Pounds (£50).
The coins are legal tender but are not intended for circulation. They are targeted at bullion investors or collectors who appreciate the special editions as pieces of art. The mint makes a distinction between plain "bullion" coins (issued in Brilliant Uncirculated grade) and proofs; the "bullion-grade" coins have textured backgrounds of both the obverse and the reverse designs and use the generic "authoritative" design, while proofs are typically "one-year" types. They are usually issued in parallel with other denominations/sizes having the same reverse designs.
Britannia as a symbol - the female personification of Great Britain - has been depicted on British coinage for centuries. The bullion series called Britannia has been issued in gold since 1987 and in silver since 1997; it has a "definitive" depiction - used on bullion coins (Brilliant Uncirculated grade), as well as “Britannia, the Changing Face of Britain” - a series of one-year designs used on proofs made for collectors, such as this one.
The mint says about it:
An unwavering symbol of strength and resilience graces a UK coin as we pay tribute to Britannia, the female personification of Britain, with a modern interpretation of the icon. Nearly 2,000 years ago, a figure was shaped to symbolise a nation and its people. Each year, a new artist reimagines Britannia for UK coins, bringing a fresh take on the changing face of Britain.
French artist Marie-Alice Harel, an award-winning author and illustrator, has created a modern interpretation of Britannia for this 2024-dated coin. | 
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