In 2006, to celebrate the 80th Birthday of Queen Elizabeth II, the Royal Mint released a very Limited Issue 80th Birthday Piedfort £5 Five Pound Silver Proof Coin struck in solid .925 Sterling Silver with 24 Carat Gold Highlights.
The reverse design is a fanfare of regal trumpets highlighted in 22 Carat gold with the inscription "Vivat Regina", with the dates "1926" and "2006", designed by Danuta Solowiej Wedderburn.
The obverse design is a regal portrait of Queen Elizabeth II designed by Ian Rank Broadley.
These legal tender coins have been struck to proof quality using specially prepared dies and highly polished blanks.
Piedforts are coins which have been specially struck on thicker than normal blanks. As their name suggests they are closely associated with France, where from the twelfth century they were apparently issued by the Kings as presentation pieces.
In Britain the practise of striking piedforts is later and less frequent, but medieval and Tudor examples are known.