The 75-year-old royal donned her rarely seen Diamond Thistle Brooch to attend the moving church service alongside her husband, the new King Charles III. The brooch was originally one of the Queen Mother's go-to pieces and she would often pin it to her hat for formal visits. The jewel was later passed on to the Queen when her mother passed away in 2002, who then presented it to Camilla.
WATCH: Queen Consort Camilla arrives at Buckingham Palace
It's not known when the brooch was loaned to Camilla, but the Duchess didn't debut it publicly until 2015. It is still a fairly rare piece, and we haven't seen the royal wear it very often.
She memorably sported it during a Burns Night address back in January 2021.
The Queen Consort was aptly dressed for Monday's service, sporting a coat dress, feather embellished hat, leather clutch and a mid-heeled court shoe.
Queen Consort Camilla sported her Diamond Thistle Brooch
She had donned the very same coat dress for the Duke of Edinburgh's funeral. Her go-to three-string pearls, a gift from her husband King Charles, adorned her neck.
The King led members of the royal family on foot behind the Queen's coffin, including Prince Edward, Prince Andrew and Princess Anne. Meanwhile, the Queen Consort and other members of the monarchy followed behind in cars.
Camilla looked elegant in a feathered hat and black jacket
After the procession, Charles will hold audiences with First Minister Nicola Sturgeon and Alison Johnstone, the Presiding Officer of the Scottish Parliament.
Words of sympathy will be expressed by the Scottish Parliament when Charles and Camilla attend to receive a motion of condolence, with the King replying.
The Queen Mother wearing her diamond thistle brooch in 1946
The eventful day is set to conclude with a historic tradition known as the Vigil of the Princes, which sees senior members of the royal family "stand guard" around the coffin.
The Vigil of the Princes is a long-standing tradition, honoured ever since the death of King George V in 1936, and was last carried out during the Queen Mother's funeral in 2002.
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