Princess Kate cut a sombre figure as she joined the rest of the royal family to mark Remembrance Day on Sunday.
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The royal looked elegant and poised in a stunning pleated black coat dress from Catherine Walker which she elevated further with a bespoke Philip Treacy hat.
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Kate completed her look with a pair of diamond-encrusted pearl drop earrings that previously belonged to her late mother-in-law, Princess Diana – and she also debuted another spectacular piece of jewellery.
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Prince William's wife was seen wearing a new brooch sold by Bentley & Skinner. The Art Deco style piece is a rectangular shape beset with diamonds.
Kate debuted her new brooch on Remembrance Sunday
The corners have been cut away to give it a distinctive shape with a central round-cut diamond at its centre and baguette-cut diamonds at the top and bottom.
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According to the Bentley Skinner website, the total estimated diamond weight if 4.5 carats. It was made around the 1920s and "captures the glamour and elegance of the Jazz Age".
The beautiful item was sold back in January - Kate's birthday month
And it seems Kate could have been given the brooch to mark her landmark 40th birthday. Royal watcher UFO NO More has further revealed that the item was up for sale in January 2022 – Kate's birthday falls on 9 January – for £14,500.
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While it's not known who purchased the brooch, it's likely to have been a gift from someone close to the Princess; perhaps her husband Prince William, King Charles and Queen Consort Camilla, or the Middleton family.
The Prince and Princess with the late Queen
There is also a chance that Kate received the brooch from the late Queen, with the Princess quietly choosing to honour the late monarch at the poignant event.
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In celebration of Kate's 40th earlier this year, Buckingham Palace released three beautiful portraits of the Princess taken by Paolo Roversi.
Kate stunned in her 40th birthday photographs
In a new interview with the Italian publication Corriere Della Sera, Paolo revealed that in order to get the three images, he took "250 shots almost all in black and white." That number was winnowed down to "about 70," and eventually to the three that were shared with the public.
Prince William, Prince George, Princess Charlotte, and Prince Louis even helped to make the final selection.
Her family helped chose the final pictures
Paolo also shared that Sarah Burton of Alexander McQueen "chose the dresses" and that there is another "secret" image of Kate, which was taken while she was dancing on set.
"In the end I wanted to take pictures in motion," he revealed. "So with that wonderful wide skirt I made her dance in front of my camera, a kind of accelerated waltz mixed with a pinch of rock'n'roll. And it's a secret image for now."