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.
In 2009, the Royal Mint re-issued the anniversary Britannia design initially used in 1997 to mark the tenth year of the Britannia bullion coins range, which was also the first issue of silver Britannias (they were only gold before). The design is known as The Charioteer and depicts Britannia standing whilst driving a two-horse chariot in the manner of the warrior queen Boudicca (Boadicea).
The composition of the coin is 91.77% gold alloyed with 8.23% silver. The coin was issued as "bullion" (in Brilliant Uncirculated grade) and in Proof FDC grade in mint sets. | 
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