In 2008 the Royal Mint released a very special Limited Issue Piedfort Silver Proof 4 Coin Collection all struck in solid .925 Sterling Silver.
The set includes two Piedfort £5 Five Pound Silver Proof Coins, the 450th Anniversary of the Accession of Elizabeth I and 60th Birthday of Prince Charles of Wales.
Also included in the set is the Piedfort Olymic Games Centenary £2 Two Pound Silver Proof Coin and the Royal Shield of Arms £1 One Pound Silver Proof Coin.
The obverse of all the coins have the portrait of Her Majesty Queen Elizabeth II 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.