There’s something different about Kate Middleton‘s latest look!

The Princess of Wales, 40, sparkled in the Lotus Flower tiara at a Buckingham Palace reception on Tuesday night, joining Prince William, King Charles III and Queen Camilla to host the Diplomatic Corps for the first time in three years. Kate was radiant in the delicate floral headpiece, which she tucked into straight, sleek strands teased at the crown, face-framing layers slicked behind her ears.

The subtle style marked the first time that Kate ever wore her hair completely down with a tiara. The Princess of Wales made her tiara debut on her wedding day in 2011, slipping Queen Elizabeth‘s Cartier Halo tiara onto a half-updo with loose curls. Her next tiara wear would be a year and a half later, when she wore the Lotus Flower to a diplomatic reception at Buckingham Palace with her tresses arranged in a similar way. The royal then shifted to chignons, which would dominate as her go-to tiara hairstyle for the next seven years.

It’s been a glittering fall for the Princess of Wales, as Tuesday night was her second time in a tiara in two weeks. On Nov. 22, Princess Kate made her tiara debut as the Princess of Wales in Queen Mary’s Lover’s Knot at the Buckingham Palace state banquet honoring South African President Cyril Ramaphosa

The choice was thoughtful for the special occasion, as the regal headpiece was also a favorite of her mother-in-law, Princess Diana, her predecessor as the Princess of Wales.

According to The Court Jeweller, Queen Mary’s Lover’s Knot tiara is over 100 years old. It was originally commissioned from the jeweler Garrard by Queen Mary, Queen Elizabeth‘s grandmother, in either 1913 or 1914. The pearl-drop design is replica of a tiara owned by Mary’s own grandmother, Princess Augusta of Hesse, who (like Kate!) was known as the Duchess of Cambridge.