The Duchess of Cambridge goes without her famous sapphire and diamond engagement ring at Commonwealth Games

The Duchess of Cambridge was without her most famous piece of jewellery when she attended the Commonwealth Games on Tuesday.

Kate made a stylish arrival dressed all in white – her trusty Alexander McQueen suit – but it was the absence of her engagement ring which puzzled some royal watchers.

The duchess now wears the sapphire and diamond cluster ring once owned by Diana, Princess of Wales, but it was missing from her left hand in Birmingham.

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Instead Kate wore just her yellow Welsh gold wedding band, her diamond eternity ring also gone from her finger.

She also accessorised with her diamond earrings and pendant from Mappin & Webb, a set that has been a staple in her wardrobe for many years now.

Photographers captured the lack of royal rings as the Cambridges watched the swimming, hockey and gymnastic events in Birmingham on day five of the games.

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They also attended an event at the University of Birmingham put on by SportsAid House, of which Kate is royal patron, on the sidelines of the games – Princess Charlotte's first official engagement without her siblings.

It's highly likely Kate chose to leave her engagement ring at home in case the opportunity to join in any sporting events arose, the risk of the priceless jewel slipping being too great.

On Sunday when Kate joined Great Britain's SailGP Team in Plymouth, she took off the sapphire ring when she changed into a wetsuit to join the crew on board the catamaran.

The duchess has previously gone without her engagement and eternity rings on other physical outings and at those where hygiene is a factor.

In January 2020, Kate went without the sapphire and diamond sparklers to visit the Evelina London Children's Hospital in London.

Interestingly at that event, too, Kate also wore her Mappin & Webb jewels.

The reason then was simple – all visitors to hospitals must adhere to strict hygiene rules and, as Kate was due to visit multiple wards housing young patients, she decided to keep her jewellery to a minimum to avoid the spread of germs.

Each time a visitor enters a hospital ward and treatment area they must wash their hands and larger, more ornate rings are likely to carry more germs than simple pieces.

In 2018, Kate chose not to wear her engagement ring when she visited the Great Ormond Street Hospital's Mittal Children's Medical Centre.

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And during the coronavirus pandemic lockdowns throughout 2020, the engagement ring was absent in a series of photos shared by Kensington Palace of Kate working from home.

The most likely reason? Kate had simply taken off the larger rings to keep her fingers clean and to prevent the spread of germs.

Rings that have gemstones – such as Kate's sapphire and diamonds – are prone to get soap, hand lotion and germs stuck in between the grooves and prongs.

It's also possible the two rings are in for professional clearing or repairs, to ensure the structural integrity of the diamonds.

The duchess's engagement ring was made by Garrard, which was appointed Crown Jeweller in 1843.

The jewel was chosen by Lady Diana Spencer when she became engaged to Prince Charles in February 1981.

Diana had selected the ring out of a catalogue in a break from royal tradition, instead of having it custom-made.

The ring features a 12-carat Ceylon sapphire surrounded by 14 solitaire diamonds, all set in 18-carat white gold.

Two years after the royal wedding, Princess Diana made a slight change to her engagement ring, adding six prongs to the existing eight in 1983, to ensure the structural integrity of the sapphire.

Prince William presented the future Duchess of Cambridge with his mother's ring when he proposed while on safari in Kenya in 2010.

Speaking of the meaningful piece of jewellery, Prince William said: "It's my mother's engagement ring, so of course it's very special to me, and Kate's now very special to me, so it was only right to put the two together."

Kate said, "It's beautiful. It's very, very special".