The Duchess of Cambridge decided to wear a diamond and pearl Cambridge tiara, which was once owned by Princess Diana, for a Diplomatic Reception at the Buckingham Palace on Tuesday, held annually by monarchs. Kate Middleton has worn a tiara only thrice before.

The tiara was initially made for Queen Mary in 1914 in the design of her choice, out of diamonds and pearls her family owned, Daily Mail reported. The tiara was a copy of the one owned by Queen Mary’s grandmother -- Princess Augusta of Hesse, who married the first Duke of Cambridge, the seventh son of King George III, in 1818. In her will, Queen Mary handed down the tiara to Queen Elizabeth who even wore it to an event in 1955.

In 1981, Queen Elizabeth gifted the tiara to Princess Diana, Prince William’s mother. In 1985, Diana wore the tiara to an official visit to Washington with Prince Charles. The tiara is said to be pretty heavy, and reportedly gave Diana headaches whenever she wore it.

It was not confirmed if the tiara, which is also known as the Cambridge Lover's Knot, was handed down to Middleton or given as a loan, Daily Mail reported.

This is not the only piece of jewelry belonging to Diana that Middleton has worn. William had gifted her a diamond and sapphire ring that belonged to Diana on the couple's engagement.