Despite being best known for being worn by Kate Middleton on her wedding day, she was not the first member of the Royal Family to wear it, and it has a long and rich history. Made in 1936, this pretty piece was bought by the Duke of York for his wife three weeks before he became King George VI, and she became Queen Elizabeth.
It was either not to her taste, or did not fit with the life of a new Queen, and she was only photographed in it once before moving on to grander pieces.
She passed it on to her daughter, Princess Elizabeth, as an 18th birthday gift in 1944. However, the Queen has never worn it publicly.
Her Majesty loaned it to her younger sister, Princess Margaret, and she wore it often in her youth.
However, once she had the Poltimore & the Lotus Flower at her disposal, the Cartier Halo fell by the wayside.
While the Duchess has worn the earrings again, the tiara is now back in the vault, awaiting another outing.
Designed by Cartier, this diamond ‘halo’ tiara is formed of a band of 16 graduated scrolls, set with 739 brilliants and 149 baton diamonds.
Each scroll is divided by a graduated brilliant and with a large brilliant at the centre.
How many tiaras are there in the royal collection?
There are dozens of priceless tiaras owned by the Queen and other members of the Royal Family.
Many of the British aristocracy also own tiaras, wearing them at state banquets and on wedding days.
As well as tiaras currently in existence, there are a couple which have been dismantled to make other diadems.
This includes The Surrey Fringe and The Nizam of Hyderabad.
Some tiaras have formed part of iconic moments in the history of the Royal Family. The Greville Emerald Kokoshnik for instance, was worn by Princess Eugenie on her wedding day to Jack Brooksbank in 2018.
Similarly, the Queen Mary Diamond Bandeau was admired around the world thanks to it being the choice of Meghan Markle for her wedding to Prince Harry in 2018.
And it is the Lover’s Knot that is most often seen today, as it is a favourite of the Duchess of Cambridge.
It was closely associated with Diana, Princess of Wales during her marriage to Prince Charles, so holds special significance for Kate.