It’s been over a decade since Kate, Princess of Wales, and Prince William’s engagement, but the dazzling 12-carat oval sapphire engagement ring that marked the occasion remains a phenomenon. The iconic ring once belonged to William’s late mother Diana, Princess of Wales, which then-Prince Charles used to propose in the Eighties. It dates back to the 19th century, when Prince Albert had a sapphire-and-diamond brooch created for his wife, Queen Victoria. It has been passed down through royal generations ever since. However, while the history of the piece is well-known, its current usage remains quite private, with the royals staying “tight-lipped about the day-to-day locations and routines regarding their jewellery,” according to an expert.

Lauren Kiehna, historian and editor of the daily blog The Court Jeweller, explained members of the Royal Family take extra care when it comes to their priceless heirlooms.

She told the most recent episode of the Royally Obsessed podcast: “Royals are pretty tight-lipped about the day-to-day locations and routines regarding their jewellery. Royal jewellery pieces have been the target of thieves for generations, so we really don’t know that much about the way they store or care for their most worn jewels.

“It’s happened in recent memory too. The Norwegian Royals had heirloom jewels stolen from Garrard in broad daylight in 1995. And you might remember Fergie had diamonds stolen by a baggage handler when she flew from New York to the UK in the Nineties.

“We generally know there are safe places for jewellery storage in most royal residences. We also know Kate has been at least a little concerned about the safety of her ring in the past. She even mentioned it in their engagement interview.”

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Speaking on their podcast at the time, the hosts of Royally Obsessed — Rachel Bowie and Roberta Fiorito — discussed the clip, and Ms Bowie said: “I just want to know was she really wearing her engagement ring?”

Ms Fiorito added: “It must be a stand-in, right?”

Ms Bowie responded: “Yes, there’s no way, like, who would allow that? There’s not enough insurance on that ring and it’s irreplaceable. In the screengrabs, she has a big rock on her finger, what else could it be?”

Ms Fiorito speculated that the couple was “that confident in her scuba abilities” they believed Kate would be able to retrieve it. “If she dropped it, she would find it,” she said before the pair concluded the ring could be “a tight fit” on the royal’s finger.

Now, an anonymous source has given more insight into why Kate may have been unable to part with her infamous ring.

They told the most recent episode of the podcast: “The royals follow a mantra that the safest place for a ring when travelling is on the hand.”

While the insider did not know “exactly what happens” when they are not at home, Ms Fiorito said the mantra “explains the Belize” video.

However, Ms Bowie said: “But I still feel like it’s not that safe if it’s on the hand in a deep scuba dive.”

And during more recent outings, the Princess has been spotted not wearing the ring.

For their first engagement of the year, Kate and William travelled to Liverpool to open the new Royal Liverpool University Hospital.

The pair delighted fans, who had gathered to get a glimpse of the future King and Queen, with selfies and their matching outfits.

Kate wore a tartan Holland & Cooper coat with a navy belted dress and matching heels. She accessorised with her Mulberry Amberley bag and sapphire earrings that matched perfectly her engagement ring — which she temporarily removed during her visit.

The Princess’s reason for removing the band was down to health and safety, “hygiene reasons” said Ms Fiorito, who conceded that the royals’ jewellery habits may never truly be known.

*This story has not been edited by The Infallible staff and is auto-generated from a syndicated feed.