King Charles' robes to weigh over 6 kg for coronation, his crown will add an extra 2 kg

On Saturday (May 6), King Charles III will be wearing heavy golden robes for the moment of crowning. Prince William will assist his father and help him place the ceremonial robes. The monarch's investiture attire will consist of the Supertunica, the Imperial Mantle, and the Royal Stole along with the St Edward's Crown.

Supertunica is a long shimmering gold-sleeved coat created for George V in 1911. It has been worn by monarchs at successive coronations including late Queen Elizabeth II. It weighs about 2kg and is made of gold silk threads, wrapped in thin pieces of gold or silver gilt metal. Its best feature is stylised arabesques embroidery and floral motifs.

On top of Supertunica, Britain's monarch will wear a floor-length cloak called the Imperial Mantle. It fastens across the chest with a golden eagle clasp.

The priest-like mantle was made for George IV in 1821 and weighs about 3 to 4 kg. It is embellished with beautiful motifs like fleur-de-lis and imperial eagles along with national floral emblems of red-pink roses, blue thistles and green shamrocks. Queen Elizabeth II also wore it during her coronation in 1953.

During the crowning ceremony, the Archbishop of Canterbury will place the 2 kg St Edward's Crown on Charle's head. And, that will be the first and only time he will wear that crown, in line with royal traditions that reserve the crown exclusively for the occasion.

It was originally made for the coronation of Charles II in 1661 and later worn by Queen Elizabeth II during her coronation in 1953.

Monarchs in the modern era have consciously opted to reuse some garments, just as Charles has. However, going a step further, he has decided to reuse the coronation sword belt and glove, which are usually made new for every ceremony.

The move is aimed at making the event more sustainable. He will be reusing the belt and glove worn by his grandfather George VI - the last male monarch.

"It was the King's personal decision", Caroline de Guitaut, deputy surveyor of the King's Works of Art at the Royal Collection Trust told CNN, adding that the items remain in "remarkable condition".

"And it's in keeping with this idea of sustainability and efficiency to reuse these pieces," she added.