The Queen Consort has unveiled her new cypher which will feature on her personal letterheads, cards and gifts.
The monogram was created with the help of a former Benedictine monk who later worked in America's Silicon Valley.
It appears more ornate than the King's cypher, which is being used on Government buildings, state documents and new post boxes.
Selected from a series of designs, the cypher is the Queen Consort's personal property.
It is expected to be seen for the first time in public on Thursday when featured on the cross she will lay at Westminster Abbey's Field of Remembrance.
Ewan Clayton, professor of design at the University of Sunderland, helped create the design in collaboration with the artist behind Charles' monogram, Tim Noad, who is a heraldic artist and calligrapher at the College of Arms in London.
The Queen Consort's cypher features the initials “CR” below a representation of the Crown, incorporating C for Camilla intertwined with R for Regina – Latin for Queen.
Professor Clayton, who trained as a calligrapher, lived as a Benedictine monk at Worth Abbey in Sussex in the mid-1980s.
He was later hired as a consultant to work at Xerox's Palo Alto Research Laboratory, in California's Silicon Valley, which helped develop Ethernet and the laser printer.
The academic is a core member of staff at the Royal Drawing School, which Charles helped establish, and is a visiting lecturer in calligraphy at a number of academic institutions.
The King's cypher, also featuring the intertwined letters CR, was revealed at the end of September.
It has replaced the ER cypher used during the late Queen's 70-year reign.
It will be used on government buildings, state documents, uniforms and some post boxes.
It will also be used by the royal household for franking mail and Buckingham Palace’s Court Post Office used the cypher on the first items of post at the end of September.
The post room deals with around 200,000 items of mail each year, including invitations to events and responses to letters and cards.
The new monogram is the first of many changes the public will see following the death of the Queen.