King Charles III’s official monogram unveiled alongside Queen Elizabeth's memorial stamps

His royal cypher shows a crown and the initials C and R

The new cypher that will be used by King Charles III. PA

King Charles III's official monogram has been revealed for the first time and is set to be a common sight across Britain in the coming years.

And four stamps featuring portraits of Queen Elizabeth II ― the first set to be approved by her succcessor — will be released in her memory on November 10.

Royal cyphers are a symbol of the monarch and are displayed on a variety of government buildings, official documents and police officers' uniforms.

They are often associated with the Royal Mail's famous red post boxes and are useful for identifying the reigning monarch of the era.

The new cypher features the king’s initial “C” intertwined with the letter “R” for Rex — Latin for king — with “III” within the R to represent King Charles III, and the crown above the letters.

Queen Elizabeth's cypher — “EIIR” — was below an image of the St Edward's Crown.

The cypher and stamps were unveiled as the royal period of mourning for Queen Elizabeth II ended, marking seven days since the late monarch's funeral in Westminster Abbey. Flags at royal residences will remain at half-mast until 8am on Tuesday.

The new stamps will feature images of the late monarch through the years.

A photograph taken by Dorothy Wilding in 1952 to mark her coronation features on second-class stamps.

The first-class stamp shows a photo taken by Cecil Beaton in 1968, in which the monarch is standing in her admiral's cloak with her head tilted to the left.

A portrait taken in November 1984 by Yousuf Karsh will appear on £1.85 stamps, and a photo taken by Tim Graham in 1996 while the Queen attended a banquet at Prague Castle during her visit to the Czech Republic will be the image on the £2.55 stamps.

"Today we are unveiling these stamps, the first to be approved by his majesty the king, in tribute to a woman whose commitment to public service and duty was unparalleled in the history of this country," said Royal Mail chief executive Simon Thompson.

The UK's new monarch travelled to Scotland soon after the queen’s funeral last Monday, with the period of royal mourning lasting for seven days after the queen’s burial.

The monogram is King Charles’s personal property and was selected by him from a series of designs prepared by the College of Arms.

A Scottish version features the Scottish crown, and was approved by Lord Lyon King of Arms.

It will be used by government departments and by the royal household for franking mail. The decision to replace cyphers will be at the discretion of individual organisations.

The process is likely to be a gradual one and in some instances the cyphers of previous monarchs can still be seen on public buildings and street furniture, especially post boxes.

The College of Arms, which designed the cyphers, was founded in 1484 and is responsible for creating and maintaining official registers of coats of arms and pedigrees.

The heralds who make up the college are members of the royal household and act under Crown authority.

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