Author Allan Mallinson has paid tribute to Princess Diana on the 24th anniversary of her passing with a photo that is believed to have never been seen before.
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Allan is a former British Army officer, and is known as the author of the Matthew Harvey series of books.
WATCH: Remembering Princess Diana
The 72-year-old posted the picture from when he met the late royal as she was sitting for a portrait for when she was the Colonel-in-Chief for the 13/18th Royal Hussars.
Diana looked beautiful in a flowing black dress, and the author highlighted her beautiful brooch that he had purchased from Garrards'.
"As it's the day (1997), I thought I'd post this photo, which I don't think has ever been published," he wrote.
"Sitting for her portrait as Colonel-in-Chief 13/18H. I had just brought the newly made brooch from Garrards'."
Allan posted this unseen image of the late royal
He then shared a closer image of the brooch, which was in the style of a royal insignia. When one fan enquired about the item, Allan revealed that it was returned to the regiment following the Princess of Wales' death, and is currently on display at the Discovery Museum in Newcastle-upon-Tyne.
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Fans posted heartfelt messages remembering the late Diana, as one said: "Diana was so beautiful. What a pity she was taken from us way too soon. May the Lord give her peace & rest & love for her soul."
A second added: "She was truly the most beautiful woman - I miss her," while others called her "stunning" and "beautiful".
Among the tributes made to Diana this year, her brother, Charles Spencer, posted a social media image of the flag flying at half mast at Diana's family home, Althorp House.
And the gardens of Kensington Palace were specially opened to the public on Tuesday to mark the 24th anniversary of her death. The gardens feature a statue of Princess Diana, which was unveiled last month by the Duke of Cambridge and the Duke of Sussex.
Tributes have been left for Princess Diana outside of Kensington Palace
Due to the pandemic, Kensington Palace and its gardens are operating on reduced opening days and are usually only accessible to the public from Wednesday to Sunday.
But Historic Royal Palaces (HRP) said special arrangements had been made to allow visitors to view the statue from the Cradle Walk around the Sunken Garden where it stands from 3pm to 5pm on Tuesday.
Diana was tragically killed in a car crash in Paris on 31 August 1997. Her sons, Prince William, and Prince Harry, were aged just 15 and 12 at the time.
Her funeral took place on 6 September 1997 at Westminster Abbey, attended by members of the royal family and a number of high-profile celebrities. Charles delivered a moving eulogy at the service, while thousands lined the streets to pay their respects.
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