The Queen stepped out alongside her youngest son Prince Edward at Buckingham Palace on Thursday, looking beautiful in a bold orange outfit with her favourite Launer London handbag.
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As always, she added a sparkling brooch to her outfit - and like many of her jewellery pieces, her latest choice has an interesting story behind it. Her Majesty's diamond rose brooch actually originally featured on a tiara that was given to her to mark her royal wedding to Prince Philip. How lovely is that?
WATCH: The Queen wears Nizam of Hyderabad brooch at Buckingham Palace
The Cartier tiara, as well as a necklace, was gifted to Princess Elizabeth by the Nizam of Hyderabad - an Indian Prince - and they hold further special meaning since the Queen chose them herself, after being told she could select whatever she wanted at the luxurious jewellery house. Wow.
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Princess Elizabeth wearing the original Nizam of Hyderabad tiara in 1951. IMAGE: Rex/Shutterstock
The tiara featured three rose brooches, all of which Her Majesty wears much more regularly than the tiara, unsurprisingly!
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While the larger rose pin - which the Queen wore during her outing with Prince Edward - is worn alone, the two smaller brooches are usually worn as a set of two.
Wearing the two smaller brooches in 2006
And the Duchess of Cambridge has had the pleasure of wearing a piece from the Nizam of Hyderabad set too, having worn the sparkling diamond necklace with her Jenny Packham gown for the National Portrait Gallery's Portrait Gala back in 2014.
Duchess Kate wore the necklace from the set back in 2014
As for the original tiara, the Queen had it completely dismantled in the 1970s, in order to make what is now known as the Burmese Ruby Tiara, adding rubies that were also given to the monarch as a wedding gift - this time from the people of Burma.
It's said that the Queen had the tiara made because the Queen Mother was very attached to another headpiece featuring rubies in the royal collection - the Oriental Circlet tiara - which should have been passed on to Elizabeth when she became Queen.
Wearing her Burmese Ruby Tiara
But rather than take it from her mum, the Queen decided to have another made - hence the Burmese Ruby Tiara, which we still see her wearing regularly today. She memorably chose to wear it to host then-President Donald Trump for a state dinner at Buckingham Palace in January 2020.