Queen Consort Camilla and the Princess of Wales were the belles of the ball at the state banquet, which was held in honour of the South African president, Cyril Ramaphosa, on Tuesday.
Dressed in their finery and regal gowns, both the Queen Consort and Princess Kate looked sublime. However, royal fans were quick to notice the special brooches they wore.
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They were seen with the badge of the Royal Family Order showing a young Queen Elizabeth II. The small diamond-encrusted brooch, positioned on a yellow ribbon, makes up the Royal Family Order, and are usually worn by female members of the royal family at state banquets.
It is thought that a total of 15 women were granted the honour by the late Queen, an honour that was first introduced by George IV in the 1800s.
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The Queen herself was a recipient of the Royal Family Orders of her grandfather, King George V, and her father, King George VI. Previous recipients of the late Queen's honour include The Queen Mother, Princess Margaret and Diana, Princess of Wales. It is believed that King Charles will one day create his own Royal Family Order to replace his mother's.
The royal family at the state banquet on Tuesday
The Queen Consort and the Princess of Wales paid tribute to the late Queen by also wearing her jewels for their first state banquet in their new roles.
Camilla opted for the much-missed monarch’s diamond and sapphire tiara, while Kate wore a pearl bracelet belonging to the late Queen, as well as Diana, Princess of Wales's earrings.
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The pair joined the King and the Prince of Wales and more than 160 guests for a glittering white tie evening affair at Buckingham Palace in honour of the South African president.
Princess Kate sported the yellow Royal Family Order
Camilla was dressed in royal blue lace evening dress by Bruce Oldfield, the Garter sash and Queen Victoria's garter order as well as the late Queen’s family order.
Kate wore a caped, white Jenny Packham floor-length evening dress with sparkling detail on the shoulders, and her go-to tiara, the Lover's Knot. The Princess also showcased the GCVO Star and Sash, as well as the four-strand pearl bracelet belonging to the late Queen and Diana’s diamond and pearl drop earrings.