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.
Starting in 2013, the proof versions of the coin feature a different design each year, while the bullion versions of the coin - such as this one - have the classic, or "definitive" Standing Britannia reverse design.
The bullion Britannias dated 2022 were released in October 2021, with a number of new security features (introduced the year before), making them "the most visually secure coin in the world". These additions both decorate and protect the coin, just as the micro-text that borders the design states - DECUS ET TUTAMEN, or "an ornament and a safeguard". In the lower left-hand of the design, below Britannia’s flowing gown, is a trident to represent her naval history. As the viewer changes their perspective this trident becomes a padlock, emphasising the coin’s secure nature. Surface animation behind Britannia reflects the movement of waves, and fine details like the Union Flag on Britannia’s shield have been highlighted by tincture lines.
These features are also available on the one ounce, quarter-ounce and tenth-ounce fine gold editions of the coin, and the one ounce fine silver edition. | 
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