Kate Middleton Debuts New Sapphire Earrings That Belonged to Princess Diana — and Debunks a Rumor!

Kate Middleton just debuted a very special pair of earrings.

Wearing a blazer style white dress from Alexander McQueen, teamed with a navy and white Philip Treacy saucer hat at Thursday's Trooping the Colour, Kate accessorized with a pair of dazzling pair of sapphire and diamond earrings that once belonged to Princess Diana.

"This is the first time we've seen Kate wear this pair of earrings in public," Lauren Kiehna, writer of The Court Jeweller blog, tells PEOPLE, explaining why it was such a significant reveal.

For the last ten years, Kate has worn a smaller pair of sapphire and diamond earrings that there widely believed to have been fashioned using the very same pair that Kate wore for Thursday's parade. Because the original pair had not been seen since Diana's death, the rumor continued to circulate, although Kiehna was always adamant that the earrings were two separate pairs.

Chris Jackson - WPA Pool/Getty Images Kate Middleton at Trooping the Colour 2022

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"The sapphires in Diana's earrings are cabochons, and the sapphires in Kate's smaller earrings are faceted. The claim has now been fully debunked as Kate has now worn the double cluster earrings," says Kiehna, who has been writing about royal jewelry for 14 years.

Karwai Tang/WireImage Kate Middleton at the Commonwealth day Service in 2022

Diana had several sapphires in her jewelry collection. She wore these particular earrings on several occasions including to the Met Gala in New York in 1996 and also during a visit to Canada in 1991, both times paired with a sapphire and pearl choker.

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The giant sapphire was originally a brooch, gifted to Diana by the Queen Mother as a wedding present. It later became the central piece of the seven-stranded pearl necklace that became a favorite of Diana's — another piece that Kate may well have inherited but has not yet been seen.

Richard Corkery/NY Daily News via Getty Images Princess Diana at the Met Gala in 1996

While it's not clear why Kate waited until now to wear the earrings publicly, she clearly has her favorites and the smaller ones may just be easier to wear. As Trooping the Colour is so synonymous with marking history and the line of succession, it may well be that Kate thought it was the perfect time for their debut. Prince Louis' outfit also took a nostalgic turn wearing a sailor suit that his father Prince William had worn at the same event 37 years ago!

Chris Jackson/Getty Images Kate Middleton and Prince William with Prince Louis, Princess Charlotte and Prince George at Trooping the Colour 2022

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Kate paired the earrings with a sapphire and diamond necklace, which appears to be a match to the smaller and much-debated earrings. She wore the matching set for the first time to meet with the President of Ukraine in 2020 and more recently to the Commonwealth Day service at Westminster Abbey in March.

JONATHAN BRADY/POOL/AFP via Getty Images Kate Middleton meeting the President of Ukraine

One sapphire piece of jewelry that Kate never takes off is her famous sapphire and diamond cluster engagement ring, which also belonged to her late mother-in-law. William proposed to Kate with it in 2010. The ring's central faceted oval Ceylon sapphire is estimated to be 12 carats and is surrounded by 14 round diamonds.