ELIZABETH II D G REG FID DEF 50 POUNDS around the effigy of Elizabeth II facing right with a crown. On the lower end of the shoulder the initials of the engraver
Description reverse
QUARTER OUNCE FINE GOLD BRITANNIA around Britannia driving a chariot which is drawn by two horses.
Reference
United Kingdom. 25 Pounds (Gold) 2009, The Royal Mint. CoCo GB-2009-0013.