Kate Middleton wears Princess Diana's tiara to the Queen's winter party

The Duchess of Cambridge wore Princess Diana's tiara to the Queen's annual Diplomatic Reception at Buckingham Palace on Tuesday, which was attended by senior royals including the Prince of Wales and the Duchess of Cornwall.

The Duchess has worn the treasured headpiece on multiple occasions, including her wedding to Prince William in 2011, last year's Buckingham Palace winter party and most recently, for a state dinner welcoming King Felipe and Queen Letizia of Spain. This time, Kate paired it with an embellished white gown, a diamond necklace and pearl pendant earrings.

The Duke and Duchess of Cambridge arrive for the Queen’s party at Buckingham Palace

Diana was given the Lover's Knot Tiara as a wedding gift from the Queen, and it has a fascinating royal history.

Although Queen Mary's Lover's Knot tiara (which Kate wears) is often called the Cambridge Lover's Knot Tiara, they're actually two separate pieces. According to the Court Jeweller, Queen Mary commissioned jewellery house Garrard to make a copy of the original Cambridge Lover’s Knot, worn by her grandmother, in 1914. The original Cambridge Lover's Knot Tiara is currently thought to be held in an unknown private collection; the version Kate wears is the copy.

When Queen Mary died in 1953, she left her tiara to her granddaughter, Queen Elizabeth II. The Queen wore the tiara a few times, but in 1981, she passed it along to Diana.

Princess Diana wearing the tiara in 1983

Kate wasn't the only one to sparkle at the palace last night. The Duchess of Cornwall was said to be wearing the Boucheron tiara, which was once a favourite of the late Queen Mother.

The Duchess of Cornwall wears the Boucheron tiara

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