Britain's royal family revealed new details Sunday about King Charles III's coronation next month, including a new Twitter emoji based on the crown the monarch will wear at the landmark ceremony.

Charles, 74, immediately became king when Queen Elizabeth II died last September after her record-breaking 70-year reign but will be formally crowned at a May 6 service inside London's Westminster Abbey.

The three-day weekend will also feature a star-studded concert, nationwide "big lunch" and volunteering initiatives, as well as the traditional royal processions associated with the coronation.

Unveiling a host of ceremonial details, Buckingham Palace said the new emoji created to mark the historic occasion is based on the 17th-century St Edward's Crown.

The centrepiece of Britain's famous Crown Jewels and worn by Charles's late mother at her coronation in 1953, it has been altered for him to wear seven decades later.

The motif will appear on Twitter when any of various hashtags -- including #Coronation, #CoronationBigLunch and #TheBigHelpOut -- are used.

It follows royal social media channels deploying a crown-wearing corgi emoji, named PJ, for Elizabeth's platinum jubilee last year -- just three months before her death aged 96.

Corgis were the late queen's favourite canine breed.

- Scaled-down service -


The latest plans released for the coronation ceremony -- which will also see Charles's wife Camilla crowned queen consort -- confirmed it will be less elaborate than the one staged in 1953.

The royal couple will travel along a shorter procession route and break with tradition by only using the elaborate 260-year-old Gold State Coach on their return to Buckingham Palace.

The pair will make the 1.3-mile (2.1-kilometre) outward journey -- known as the King's Procession -- from the palace in the more modern, comfortable Diamond Jubilee State Coach.

It has shock absorbers, heating and air conditioning.

The service will begin at 11:00 am (1000 GMT) and is expected to be much shorter than in 1953, when it lasted almost three hours.

The palace also confirmed the priceless array of regalia from the Crown Jewels to be used during the hour-long ceremony, which will include among other elements an orb, swords and sceptres.

On Friday, it revealed over 850 community and charity representatives from across the UK have been invited to the service, which will also be attended by foreign royals, leaders and heads of state.

They include 450 recipients of the British Empire Medal -- awarded for achievement or contribution of service in local communities -- and 400 young people representing charitable organisations.