The Queen debuted a sparkling ruby tiara as she and the King hosted South Korea’s President Yoon Suk Yeol at a Buckingham Palace state banquet.
Camilla, 76, looked elegant in a red velvet evening dress by her go-to designer Fiona Claire for the white-tie dinner.
She teamed her beautiful dress with the late Queen Elizabeth II's Burmese Ruby Tiara. The sparkling diamond and ruby headpiece was one of the newest tiaras in the late Queen's personal collection.
It was made in 1973 by Garrard, using gemstones from the Nizam of Hyderabad tiara (which was originally a wedding gift from the 7th Nizam of Hyderabad), and rubies gifted to Her Late Majesty from the people of Burma.
With her feathered blonde bob in her signature blowdried style, she opted for a natural makeup look, with a pop of pink blusher and matching lipstick.
The Queen added finishing touches in the form of the late Queen's ruby and diamond necklace and similar earrings from her own personal collection.
Camilla's evening look comes after she chose a blue dress and coat by Anna Valentine with a feathered hat by Philip Treacy.
Her Majesty and the Princess of Wales displayed sartorial diplomacy as they both sported colours featured in South Korea's flag.
Kate opted for a red cape and a coat by Catherine Walker with a Jane Taylor.
The state visit began with the Prince and Princess of Wales greeting the President and Kim Keon Hee at their hotel in London, before accompanying them to Whitehall.
In Horse Guards Parade, where the King traditionally celebrates his official birthday, Mr Yoon, accompanied by Charles, inspected a guard of honour, formed by F Company Scots Guard.
Members of the Scots Guards were recently deployed to South Korea where they were training troops.
The foreign head of state walked past the two ranks of Guardsman casting his eye over the servicemen before returning to the royal pavilion with the King.
After the ceremonial welcome, the traditional carriage procession back to Buckingham Palace saw the King travel with the Korean president in the Australian state coach.
After a private lunch, the South Korea leader and his wife joined the royals to view a special exhibition in the palace's Picture Gallery of items from the Royal Collection relating to the Republic of Korea.
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