The Duke and Duchess of Cambridge concluded their special royal train tour on Tuesday evening by joining the Queen and other members of the royal family at Windsor Castle - and what a memorable moment it was!
And thoughtful Kate made sure she paid tribute to Her Majesty with her outfit, too, by wearing a pair of beautiful diamond earrings from the monarch's own collection.
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Known as the 'Diamond Frame Earrings', the Queen is thought to have loaned them to her granddaughter-in-law on a long-term basis - and Kate has worn them for a number of important occasions in the past.
Kate wore the Queen's diamond earrings
The sparkling designs feature a floral cluster at the earlobe, with a stunning teardrop of diamonds beneath.
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For Tuesday night's engagement, the Queen was joined by the Prince of Wales, the Duchess of Cornwall, the Cambridges, the Earl and Countess of Wessex and the Princess Royal, as they thanked local volunteers and key workers in the quadrangle of Windsor Castle.
The royals came together for a special event at Windsor Castle
No doubt it was a lovely moment to see Kate arrive wearing her sparkling jewels! The Duchess also wore her bespoke Catherine Walker coat that she debuted in Ireland in March, to which she added a chic faux fur collar from Troy London, worth £65.
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The Queen wearing the Diamond Frame Earrings in 2013
Kate has stunned us in a number of festive outfits during her latest royal tour - and there was one trend that stood out in particular - tartan.
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The royal rocked a number of plaid looks, from her Emilia Wickstead skirt to her enviable scarf collection - and it's safe to say royal fashion fans are swooning.
Looking beautiful in tartan!
"The Duchess of Cambridge is looking fabulous in her festive looks," one commented on the Kensington Royal Instagram page, while another added: "Obsessed with the Duchess' coat collection on this tour!"
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