The King’s new Family Order has been worn for the first time by the Queen at the Japanese state banquet.

Camilla stepped out wearing the diamond-encased miniature portrait of her husband topped with a tiny gold and enamel Tudor crown and suspended on a pale blue silk bow on her left shoulder for the glittering event in the Buckingham Palace ballroom.

The unveiling of the new King Charles III’s Family Order comes nearly two years after Charles, the longest serving heir to the throne, acceded as monarch following the death of his mother.

Family Orders badges are worn at formal evening occasions by female members of the royal family and personally bestowed by the sovereign, and are a sign of the importance of the wearer within the royal household.

The King will have privately presented the Order to his “darling wife” and Queen consort, Camilla – whom he praised in his first televised address as monarch for her “steadfast devotion to duty on which I have come to rely so much”.

The couple faced the challenge together this year of the King being diagnosed with cancer and having ongoing treatment, with the Queen urging her husband to take it easy but revealing he “won’t slow down and won’t do what he’s told”.

More than one Family Order can be worn at the same time and Camilla was also wearing the late Queen Elizabeth II’s which is mounted on a chartreuse yellow ribbon, below that of the King’s.

George IV started the tradition of presenting Family Orders – miniature portraits of the sovereign set in diamonds suspended from a ribbon – to female members of the family more than 200 years ago.

But Charles has modernised some of the elements of his own, while keeping to the traditional appearance.

His miniature portrait is painted on a synthetic material called polymin, rather than on ivory as was the tradition, and the diamonds are spare ones – existing loose jewels from the Royal Collection rather than newly acquired.

Polymin is a translucent treated plastic sheet similar in texture to ivorine, which is a synthetic ivory made from cellulose nitrate.

The diamonds are brilliant-cut and have a total weight of 10.41 carats – and the Order, designed by the Crown Jeweller Mark Appleby, was crafted in 18 carat white and yellow gold which was already in royal possession.

Charles personally selected the pale blue colour of the ribbon which is based on the bow on the Family Order of his great-grandfather King George V.

Sovereigns presenting jewelled portraits of themselves have tended to use different-coloured ribbon from other monarchs.

George V’s was pale blue, George VI’s was rose pink, and Elizabeth II’s was chartreuse yellow.

The painting of the King – depicting the monarch wearing the uniform of Admiral of the Fleet, the Sash of the Royal Victorian Order, the Garter Star and Thistle Star and the Garter Collar and Neck Orders of the Order of the Bath and the Royal Victorian Order – was by portrait miniaturist Elizabeth Meek.

Meek previously painted a miniature portrait of Charles as the Prince of Wales in 2005, and the new image was based on a photographic portrait by Hugo Burnand, taken in 2023.

Before 1820, the sovereign’s portrait set in a jewelled frame had been worn by both ladies and gentlemen at Court, but especially by female members of the royal family.

Camilla was given the late Queen’s Family Order by her mother-in-law on her 60th birthday in 2007.

The Queen Mother used to wear the Orders of both her daughter and late husband George VI, while Elizabeth II wore George VI’s Order and George V’s Order together.

The silk bow was made by the milliner Philip Treacy.