Kate attends banquet wearing Princess Diana's beloved Cambridge Lover's Knot Tiara

A little over a month after she dazzled in Jenny Packham and the Queen's Lotus Flower tiara at her first state banquet, the Duchess of Cambridge stepped out on Tuesday (Dec. 8) wearing another exquisite headpiece from the Royal Family's lustrous jewelry box. Joined by her husband, Prince William, Kate arrived to the Diplomatic Reception at Buckingham Palace wearing the Cambridge Lover's Knot tiara, a piece that was one of the late Princess Diana's go-to accessories.

Kate arrives to a banquet at Buckingham Palace wearing the Cambridge Lover's Knot tiara. Photo: © Getty Images

The pearl-and-diamond masterpiece was commissioned by Queen Mary in the early 1910s. It became one of the most famous pieces from the royal collection after the Queen loaned it to her daughter-in-law Princess Diana, on the occasion of her wedding in 1981. Diana later said the tiara was so heavy it induced a headache and she had to switch to her Spencer family tiara instead.

Princess Diana wore the pearl-and-diamond topper on many occasions after receiving it on loan from the Queen. Photo: © Getty Images

Tuesday evening's white-tie Diplomatic Reception is the main ambassadorial social event of the year in London, which "reflects the Queen’s importance in the country’s diplomatic relations." All senior members of the royal family who do not have prior engagements attend. The event is the largest reception held annually at Buckingham Palace, with more than 1,500 dignitaries invited from around 130 countries.

Prince George and Princess Charlotte's glamorous mom attended her first Diplomatic Reception in 2013, wearing a pastel-blue lace Alexander McQueen gown, the Queen's Greville chandelier earrings and the Papyrus/Lotus Flower tiara. It appears that the mother-of-two recreated the same ensemble for Tuesday's affair, but swapped the Papyrus/Lotus Flower tiara for the Cambridge Lover's Knot.

Kate's latest public appearance marks only the fourth time she has been seen in public wearing a tiara. The first time was on her wedding day in 2011, when she wore the Cartier Halo tiara, followed by the Papyrus/Lotus Flower tiara on two occasions and now she has added the iconic Cambridge Lover's Knot piece to her treasure trove.

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