Royal Mail is marking the 50th anniversary of the current design on its stamps with a new issue.
The stamp, featuring a profile of the Queen by Stoke-on-Trent-born sculptor Arnold Machin, has been reproduced in more than 130 colours since 1967.
He also designed the profile of the Queen that appeared on coins from 1968 to 1984.
A set of six stamps has now been issued featuring different stages of the stamp design.
The new stamps were issued on Monday to mark the day the Machin Definitive, as the image is known, was first issued.
It has since been reprinted an estimated 220 billion times.