Like many other mints, the Royal Mint issues bullion coins in precious metals, having much higher intrinsic value than their face value. The unusual format of twenty ounce (20 oz) silver coins are denominated as two hundred and fifty pounds (£250) and was issued for the first time in 2017 for the 20th anniversary of the silver Britannia range.
The coins are legal tender but are not intended for circulation. They are targeted at bullion investors or collectors who appreciate these special editions as pieces of art. The coins are "one-year" types issued in parallel with smaller denominations with the same reverse designs.
Britannia as a symbol 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 like this one - used on proofs made for collectors.
While firmly rooted in the times of the Romans, a modern Britannia has emerged, appearing as a symbol of design excellence in high fashion magazines and associated with all things fashionable during the ‘Cool Britannia’ phase in the 1990s. On the 20th anniversary of the silver Britannia bullion coin, fine art student Louis Tamlyn has created a contemporary reverse design, reflecting a time of political change when the eyes of the world have often been on Britain. His design also contains a trident mint mark that celebrates these important anniversaries.
This is the first silver twenty-ounce coin issued in the United Kingdom; it was released to mark the twentieth anniversary of the silver Britannia range. | 
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