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) platinum 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 coins are typically "one-year" types usually issued in parallel with other denominations with the same reverse designs.