People are saying Prince William bought Kate this ring

(Image credit: Getty Images)

Last week, the Queen hosted a reception at Buckingham Palace for the Diplomatic Corps, and Kate Middleton made headlines by wearing one of Princess Diana's most iconic tiaras.

But another, slightly less conspicuous piece of jewellery caught royal fans' eyes, namely a rather large diamond ring she wore on her right ring finger.

The reason people are talking about it, is that unlike the rest of the pieces she wore, which have been or are part of the royal collection, the origin of the ring is a bit of a mystery.

So naturally, some have concluded that it may simply have been a gift from Kate's husband, Prince William, perhaps on the occasion of their last anniversary, or her birthday in January. In any case, it's the first time she has been photographed wearing it.

The Duchess also wore the Nizam of Hyderabad necklace and matching chandelier earrings. The set belongs to Queen Elizabeth II and was a gift on her wedding day to Prince Philip in 1947 from the last Nizam of Hyderabad, Mir Osman Ali Khan.

She also wore Princess Diana's Cambridge tiara, which also belongs to the Queen, as well as her sapphire and diamond engagement ring, which belonged to the late Princess of Wales and was given to Prince William upon her passing.

Penny Goldstone

Penny Goldstone is the Digital Fashion Editor at Marie Claire, covering everything from catwalk trends to royal fashion and the latest high street and Instagram must-haves.

Penny grew up in France and studied languages and law at the Sorbonne Nouvelle University in Paris before moving to the UK for her MA in multimedia journalism at Bournemouth University. She moved to the UK permanently and has never looked back (though she does go back regularly to stock up on cheese and wine).

Although she's always loved fashion - she used to create scrapbooks of her favourite trends and looks, including Sienna Miller and Kate Moss' boho phase - her first job was at MoneySavingExpert.com, sourcing the best deals for everything from restaurants to designer sales.

However she quit after two years to follow her true passion, fashion journalism, and after many years of internships and freelance stints at magazines including Red, Cosmopolitan, Stylist and Good Housekeeping, landed her dream job as the Digital Fashion Editor at Marie Claire UK.

Her favourite part of the job is discovering new brands and meeting designers, and travelling the world to attend events and fashion shows. Seeing her first Chanel runway IRL at Paris Fashion Week was a true pinch-me moment.