When you find a tiara you love, you stick with it.

Kate Middleton brought out a royal favorite for the latest state banquet, once again dazzling in the sparkling headpiece that has become her go-to for palace glamour.

On Oct. 20, the Princess of Wales joined her husband, Prince William, to help King Charles and Queen Camilla host Sultan Haitham bin Tarik of Oman for his state visit to the U.K. at Windsor Castle. For the glamorous evening, the mother of three wore her go-to headpiece: Queen Mary's Lover's Knot tiara, which she has worn numerous times since 2015.

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Britain's Prince William, Prince of Wales and Britain's Catherine, Princess of Wales arrive for a state banquet at Windsor Castle, Windsor, on Oct. 20, 2026, the first day of a three-day State Visit to the United Kingdom by The Sultan of Oman. (Aaron Chown / POOL / AFP via Getty Images))

The 44-year-old completed her look with a flowing, sunshine-yellow gown by Elie Saab, King Charles' Royal Family Order badge and the Royal Victorian Order sash and star.

"Kate is wearing what I like to call her 'old faithful,'" royal commentator Amanda Matta told Fox News Digital.

Catherine, Princess of Wales arrives for the state banquet for Sultan Haitham bin Tarik al Said at Windsor Castle during the Sultan of Oman's state visit to the U.K. on Oct. 20, 2026. (Getty Images)

"It has truly become her signature piece of royal jewelry, and it speaks to her constancy as a part of the modern monarchy. Paired with a new beautiful gown for the formal occasion, a repeat tiara keeps the entire look from overshadowing the visiting Sultan of Oman and the true hosts of the evening: King Charles and Queen Camilla."

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"I always come back to what a perfect piece this was for Kate to pull off all those years ago when she first wore It," said Matta. "It's a very romantic piece, tying in nicely with the sentimentality of William and Kate's royal love story."

Since Kate married Prince William in 2011, she has worn five different royal tiaras, with the Lover's Knot appearing to be her favorite.

Princess Kate wore a yellow gown by Elie Saab. (POOL/AFP via Getty Images)

The sparkler is a replica of an earlier piece, Town & Country reported. According to the outlet, it was created for Queen Mary in 1913 by the House of Garrard using pearls and diamonds already owned by her family. Mary modeled it after a tiara owned by her grandmother, Princess Augusta, Duchess of Cambridge. The original tiara is believed to be held in a private collection.

The Court Jeweller reported that when Mary commissioned the piece, she "sacrificed a tiara from her own jewelry collection, the Ladies of England tiara, to make it."

Oman's Sultan Haitham bin Tarik and Britain's Catherine, Princess of Wales attend the state banquet at Windsor Castle, Windsor, on Oct. 20, 2026. (POOL/AFP via Getty Images)

When Mary died in 1953, she left the Lover's Knot tiara to her granddaughter, Queen Elizabeth II, who wore it on several occasions. In 1981, she loaned it to her daughter-in-law, Princess Diana, the outlet reported.

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The Lover's Knot was one of only two tiaras Diana was ever photographed wearing, with the other being the Spencer tiara, which belonged to her father. The outlet noted that the Spencer tiara is now owned by the late princess' brother, Charles Spencer.

Diana, Princess of Wales, wearing a cream lace gown with a scalloped neckline designed by Murray Arbeid and the Lover's Knot diamond and pearl tiara, smiles as she attends a dinner at the British Ambassador's Residence in Washington, D.C., on Nov. 11, 1985. (Getty Images)

After Diana's divorce in 1996, the Lover's Knot was returned to Queen Elizabeth II.

Queen Camilla opted for the Girls of Great Britain and Ireland tiara, which was one of the late Queen Elizabeth II's favorites. Unlike the Lover's Knot, Queen Elizabeth II wore that headpiece numerous times throughout her 70 years on the throne, People magazine reported. Camilla first wore it in 2023.

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Britain's Queen Camilla poses for a photograph ahead of a state banquet at Windsor Castle in Windsor on Oct. 20, 2026. (POOL/AFP via Getty Images)

State visits, which are coordinated between the Foreign, Commonwealth and Development Office and the royal household, aren't just about showing off the glittering crown jewels. They help strengthen ties between countries. The Omani state banquet was held in St. George's Hall at Windsor Castle while Buckingham Palace undergoes renovations.

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Catherine, Princess of Wales has slowly returned to royal duties. (Getty Images)

People reported that St. George's Hall would host 160 guests at the dinner, with a 50-meter-long table featuring 480 knives, 480 forks and 160 spoons. Following Omani tradition, an Arabic coffee lightly spiced with cardamom and rose water was prepared for guests. Two iced teas — Earl Grey and mint with rose water — and one warm cardamom-spiced tea were also served, the outlet reported.

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Princess Catherine dazzles guests at Windsor Castle with her golden ensemble. (Getty Images)

Kate has gradually returned to royal duties after announcing in September 2024 that she had completed chemotherapy. The princess announced in January 2025 that she was in remission.