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.
1997 was the tenth year of the Britannia bullion coins range, and the first time when silver Britannias were also issued. The anniversary edition was marked by a new design, known as The Charioteer, where Britannia is depicted standing whilst driving a two-horse chariot in the manner of the warrior queen Boudicca (Boadicea).
This year, the composition was 91.77% gold alloyed with 8.23% silver.
The half-ounce (1/2oz) coin was issued in Proof FDC grade in mint sets only, not individually. | 
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