Great Britain Queen Elizabeth II 1973 7½p British Explorers, Walter Raleigh, SG926a.
A very fine unmounted original gum example with gold (Queen's head) omitted. Offered with normal for comparison. A rare, iconic and famous modern British stamp error.
Pierron records only 6 mint examples.
Accompanied with a 2010 British Philatelic Association (BPA) certificate of authenticity.