The Duchess of Cambridge proudly showed off her stunning sapphire engagement ring during a formal photo call with Prince William to announce their engagement on 16 November 2010.
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But the sentimental rock that once belonged to Princess Diana could have ended up on the hand of Kate's sister-in-law, Meghan Markle. After the Princess of Wales passed away, her two sons Prince William and Prince Harry inherited some special pieces of jewellery from their late mother – and the ring was chosen by Harry.
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It is widely reported that once William's relationship with Kate progressed, Harry made the decision to give the ring to his elder brother for the proposal. It is thought that he liked the idea of the engagement ring sitting on the throne one day.
In Amazon Prime's The Diana Story documentary, Diana's former butler Paul Burrell reported that when she had passed, the boys were given the opportunity to keep an item that belonged to her as a keepsake.
Kate Middleton wears Princess Diana's engagement ring
Paul remembered that William said: "I’d like mummy’s Cartier watch, the one that Grandpa Spencer gave to her for her 21st birthday," whereas it was Prince Harry who in fact wanted to keep the engagement ring.
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Prince William proposed to Kate Middleton in 2010
Paul recollected that Prince Harry once said: "I remember when I held mummy's hand when I was a small boy and that ring always hurt me because it was so big," which is why it had sentimental meaning for him.
Princess Diana's ring is famed for its statement sapphire stone
Kate did actually have the ring adjusted once it was her engagement ring because it was too big for her finger.
So, as it transpires, Meghan Markle could have been the lucky lady to wear Princess Diana's iconic band – but it wasn't meant to be.
Prince Harry sourced the diamonds for Meghan Markle's engagement ring
Prince Harry's generosity and sentimentality has since been reflected in his choice of engagement ring for Meghan. Her special ring has multiple diamonds and each one was specially selected by the Prince; the central diamond is from Botswana, where the couple previously vacationed together, and the other two diamonds are from his late mother's personal collection.
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