In 1980 to celebrate Queen Elizabeth the Queen Mother's 80th Birthday, the Royal Mint released a special Limited Issue Queen Mother 80th Birthday 25p Twenty Five Pence Commemorative Crown Coin.
The reverse designed by Richard Guyatt depicts the Queen Mothers head in the center with a fan-fair design with Queen Elizabeth the Queen Mother August 4th 1980.
The obverse is the portrait of Her Majesty Queen Elizabeth II by Arnold Machin.