In 2012 Queen Elizabeth II celebrated her Diamond Jubilee. She became Queen on 6 February 1952 following the death of her father King George VI. It seemed a fitting time to create this illusion portrait.
It is based on a First Class postage stamp, which is described, by the Royal Mail, as being Gold/iridescent. This stamp has been in use for several years and still exists. Many new stamps were released for the jubilee year. One had the same portrait of the Queen on a pale blue background.