The Princess of Wales was visiting Dowlais Rugby Club in Merthyr Tydfil, Wales when she made a surprise confession about her sapphire and diamond engagement ring.
The rock famously belonged to Prince William's late mother Princess Diana, who picked it from Garrard due to the colour of the sapphire stone matching her eyes. After Diana's death in 1997, Prince William inherited the ring and carried it with him during a trip to Kenya with friends until finding the right moment to pop the question.
When royal fans spotted the ring on Kate's left hand during her appearance in Wales – as part of her visit to celebrate the 60th anniversary of Central Beacons Mountain Rescue – she explained: "Same ring! And it's exactly the same size, it's very special. I'm honoured to wear it, I never sadly got to meet her.
"And also now with the children and grandchildren, I think she would have loved being a grandmother so much. She'd be absolutely brilliant, we miss her every day."
Kate's latest comment may come as a surprise to many fans since it was previously reported that her engagement ring was a little too big for her hand when William proposed.
However, instead of breaking and resoldering the band itself, the Princess found a way to have the ring resized without tampering with the original design – and it's completely reversible. Jeweller G. Collins and Sons added small platinum beads inside the band to reduce its diameter, which is why the secret alteration has not been visible from the exterior.
"It would be easier to think that by adding extra platinum, or by working on something, we increase or decrease its value, however....this item of jewellery is truly unique in the fact that its provenance has increased its true value considerably, and so these minor alterations won't truly affect the price in any way," explained diamond expert Anthony French at Austen & Blake.
"Especially with the small cosmetic change being something that can also be removed, and the ring put back to its 'original' state if need be," he added.
Kate was first pictured wearing her new ring at her engagement photocall with Prince William at St James's Palace on 16 November 2010. She teamed with a coordinating blue frock from Issa.
How did Prince William propose to Princess Kate?
William revealed it took him a whopping three weeks before he decided to propose during his trip to Kenya, South Africa in 2010 – and he carried the ring around with him everywhere. "I had been carrying [the ring] around in my rucksack for about three weeks before [the proposal]," William told ITV. "Everywhere I went, I was keeping ahold of it, because I knew if this thing disappeared, I'd be in a lot of trouble."
He added that he was too afraid to ask for Kate's father Michael Middleton's blessing beforehand. During their engagement interview with journalist Tom Bradby in 2010, William explained: "Well, I was torn between asking Kate's dad first and then the realisation that he might actually say 'no' dawned upon me.
"So I thought if I ask Kate first then he can't really say no. So I did it that way round." The royal added: "I managed to speak to Mike soon after it happened really and then it sort of happened from there."
What has Prince Harry said about Princess Kate's engagement ring?
Princess Diana's engagement ring was believed to have been inherited by Prince Harry, who supposedly handed the jewel to his older brother in a sweet gesture ahead of his proposal. In his memoir Spare, the royal admitted the entire story was "nonsense" as William had asked for the sapphire after their mother died in a car crash in France in 1997.
Harry also commented on the couple's gold wedding rings, which he took the "solemn duty" of keeping safe on their wedding day. In fact, he was so intent on performing his duties that he had a foolproof way of making sure that it went without a hitch. "I couldn't have lost that ring if I’d wanted to. A special kangaroo pouch had been sewn inside my tunic. My idea, actually, that was how seriously I took the solemn duty and honor of bearing it.
"Now I took the ring from its pouch, held it to the light. A thin band of Welsh gold, shaved off a hunk given to the Royal Family nearly a century before. The same hunk had provided a ring for Granny when she married, and for Princess Margaret, but it was nearly exhausted now, I’d heard," he wrote.
When did Prince William and Princess Kate get married?
On 29 April 2011, the world was watching as Prince William and Princess Kate became husband and wife at Westminster Abbey, in front of family guests such as the Queen, Prince Philip, then-Prince Charles and bridesmaid Pippa Middleton. Kate was a stunning bride in a lace Alexander McQueen wedding dress, while William wore his red Irish Guards uniform - a decision made by his grandmother, the late Queen Elizabeth II.
RELATED: Princess Kate and Prince William going incognito on secret date nights?
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