The Duchess of Cambridge's archive of jewellery is unrivalled. From royal heirlooms to thrifty high street bargains, the wife of Prince William always knows how to amp up the glamour of any outfit with a perfectly coordinated accessory - but did you spot her sentimental necklace worn at the Queen's Platinum Jubilee?
SEE: Kate Middleton dazzles in elegant white power suit for Platinum Party at the Palace
Duchess Kate stunned royal fans in an immaculate white power suit from Self-Portrait for the Platinum Party at the Palace on Saturday.
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Complete with a fitted blazer-style bodice and elegant sheer pleated skirt adorned with regal lace, the 40-year-old royal was easily one of the best dressed royal ladies at the star-studded event.
It was the Duchess' surprising accessory that truly caught our attention, however. Kate wore a delicate diamond cross pendant necklace, which sat perfectly in the V neckline of her Self-Portrait blazer.
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The royal's diamond cross pendant is set on a delicate silver chain
It's not the first time the royal has worn the stunning pendant, with the piece believed to have been in her collection for many years.
She was spotted wearing it as far back as 2005, when she attended the wedding of Hugh van Cutsem and Lady Rose Astor.
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Historically, the symbol represents the Christian cross, and could potentially have been given to the Duchess as a gift, perhaps even in her childhood years.
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The Duchess of Cambridge, like the rest of the royal family, is part of the Protestant Anglican church. The Protestant church does not ban the wearing of the cross symbol, though it is typically believed that the wearing of a cross symbol with a corpus (or crucifix), is a symbol of the Catholic faith.
The Duchess was beaming as she enjoyed the Platinum Party performances
The mother-of-three was joined by her husband, Prince William, and their three children; Prince George, Princess Charlotte and Prince Louis at the Platinum Party.
Styling her glossy chestnut locks in a side-swept look, the royal sported a glowing complexion as she combined a brown smokey eyeshadow with a touch of mascara, rosy blusher and nude lipstick.
As for her husband, Prince William made a dapper appearance alongside his wife in a blue suit complete with a crisp shirt and tie.
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