The duchess in a sleek Jason Wu midi-dress. Picture: AP

Like many married women, the Duchess of Sussex wears her engagement and wedding rings on her ring finger. But recently, eagle-eyed onlookers have noticed a third ring on the same finger.

And there might be a very significant reason for it, according to The Express.

When Prince Harry proposed to her, she was gifted a trilogy engagement ring. Designed by Harry, the ring had a centre stone from Botswana and two diamonds on either side which belonged to Princess Diana, the newspaper reported.

“Meghan’s ring is arguably the most famous contemporary engagement ring in the world today," Eddie LeVian, CEO of jeweller Le Vian told the publication.

“Prince Harry chose a trilogy engagement ring for Meghan, with a centre stone from Botswana and two diamonds on either side which came from his late mother Princess Diana’s jewellery collection.

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Today, we are excited to be able to announce details for the Duke and Duchess of Sussex’s upcoming tour to Africa! 🇿🇦🇧🇼🇦🇴🇲🇼 • In just two weeks, Their Royal Highnesses will embark on this official tour focusing on community, grassroots leadership, women’s and girls’ rights, mental health, HIV/AIDS and the environment. This programme has been many months in the making, and The Duke and Duchess are eager to focus their energies on the great work being done in Southern Africa. From meeting with Archbishop Desmond Tutu to joining ‘Waves for Change’ on Monwabisi Beach, the South Africa programme will be educational and inspiring. The Duke is especially proud to continue the legacy left by his mother with her work in Angola as he joins Halo Trust again in an effort to rid the world of landmines. HRH will also travel to Malawi where he will check in on the British Army’s partnership with African Parks and will be working on the ground supporting local communities. The Duke is particularly proud to be able to deliver an exciting new initiative, a Queen’s Commonwealth Canopy three-country partnership which he designed and consulted with Governments in Namibia, Botswana and Angola to protect forest and wildlife corridors around the Okavango Delta. The Duchess will be working with local organisations to promote women and girls’ health and education, entrepreneurship and leadership. With such a textured culture and history, Their Royal Highnesses are grateful for the opportunity to connect with those on the ground in Southern Africa and to be inspired by the work being done and learn how they can be better supported. As President and Vice President of The Queens Commonwealth Trust and The Duke’s role as Commonwealth Youth Ambassador, The Duke and Duchess cannot wait to meet with young leaders mobilising change and adding to the beauty of these Commonwealth countries 🇿🇦🇧🇼🇦🇴🇲🇼 • “We look forward to seeing you soon!” • Photo ©️ PA images / Tim Graham - Getty Images / @Sentebale /@AfricanParksNetwork / @YouthAlert

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“In this way he created a new jewel with a beautiful sense of history," added the jeweller.

Upon tying the knot, Prince Harry sealed their vows with a band which is thought to be made of Welsh gold, and follows the tradition of other royals - including Queen Elizabeth II and the Duchess of Cambridge.

Many speculate that the third ring could be a push present from Harry. She was spotted wearing it soon after the birth of their son, Archie Harrison.

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Spotlight on: Smart Works We are proud to be supporting a very special initiative this autumn for @SmartWorksCharity! After quiet visits to Smartworks over the last year, The Duchess was moved by the impactful work being done by this non profit organisation that helps women into the workforce, equipping them with both the skills and clothes they need to feel job-ready. Throughout her visits she noticed that while the donations were plentiful, they were also notably a combination of mismatched items and colours which weren’t always the right stylistic choices or sizes that didn’t necessarily “suit” the job at hand: to make a woman feel confident and inspired as she walked into her job interview. As a result, launching this autumn, The Duchess will be supporting a collective to help equip the women of Smart Works with the key workwear essentials they need as they enter into the workplace. This initiative is supported by four generous brands who share the vision to empower the women of Smart Works to look and feel 💯 as they bravely venture in to what can often be a daunting environment for those who have been out of the job market. The brands have come together to work towards this united force for good, “[reframing] the idea of charity as community,” as The Duchess writes in a piece for this month’s British Vogue. They will follow the 1:1 model where an item from the collection purchased is an item shared with a woman of Smart Works because “not only does this allow us to be part of each other’s story; it reminds us we are in it together.” For more information on how you can be part of another woman’s success story visit @smartworkscharity. Special thanks to: @JohnLewisandPartners, @MarksandSpencer, @MishaNonoo, @InsideJigsaw for supporting this very special organisation. And to find out more, read the September issue of @BritishVogue and stay tuned for more exciting updates this autumn. Photo©️SussexRoyal

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According to Harper’s Bazaar, the pave-set ring is embedded with the birthstones of Archie, Meghan and Harry.

Meghan has a soft spot for sentimental pieces, and has taken to wearing some very special pieces from the late Princess Diana's private collection. These include Diana's gold butterfly earrings, a simple gold bracelet and an aquamarine cocktail ring.