In 2010 to celebrate the Capital Cities of the United Kingdom, the Royal Mint released a very special Limited Issue London Piedfort £1 One Pound Silver Proof Coin struck in solid .925 Sterling Silver.
The reverse of the London Silver Proof Coin shows the coat of arms which belongs to the Corporation of the City of London – the 'Square Mile' presided over by the Lord Mayor of London.
The arms of the City are blazoned as follows:
Argent a cross within the first quarter a sword erect point upwards gules.
This means a white or silver background with a red cross and an upright red sword in the top left, and is usually explained as combining the symbol of the City's patron saint with that of England's: the red cross of St George, with the sword as a symbol of St Paul's martyrdom.
The obverse design is the stunning portrait of Her Majesty Queen Elizabeth II by Ian Rank Broadley.
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.
These legal tender coins have been struck to proof quality using specially prepared dies and highly polished blanks.