2 Pounds - Elizabeth II St. Paul's Cathedral, Silver Piedfort

The 2005 St. Paul's Cathedral two-pound piedfort was issued to mark the 300th anniversary of the cathedral's completion in 1710, when Sir Christopher Wren — then 78 years old — reportedly climbed to the top of the dome himself to inspect the final stonework. Piedforts from the Royal Mint are struck at double the standard thickness using a separate, carefully prepared planchet, requiring multiple slow-pressure strikes rather than a single production blow.

Wren's bill for the full project came to roughly £733,000 over 35 years of construction, funded through a coal tax levied on London imports.