Sophie, the Duchess of Edinburgh Wears One of Kate Middleton's Favorite Tiaras to State Banquet

Sophie, the Duchess of Edinburgh is sparkling in one of Kate Middleton's top tiaras at the state banquet at Buckingham Palace.

On June 25, the Duchess of Edinburgh, 59, shimmered in the Lotus Flower Tiara at the diplomatic dinner held in honor of Emperor Naruhito and Empress Masako of Japan's state visit to the U.K. The style choice was significant as Sophie's first time wearing the Lotus Flower Tiara, expanding her royal rotation.

Prince Edward's wife has previously glittered in two aquamarine tiaras and her all-diamond wedding tiara, made up of four detachable diamond anthemions which were reportedly sourced from one of Queen Victoria’s crowns.

Sophie completed her look at the latest state banquet with even more diamonds, sporting Queen Elizabeth's Pear-Shaped Diamond Drop Suite. Sophie has worn the necklace and earrings combo before for the state banquet held in honor of then-president Donald Trump's state visit to the U.K. in June 2019, according to The Court Jeweller. 

The Lotus Flower Tiara was most recently taken out of the royal vault for Princess Kate to wear at the Diplomatic Corps reception at Buckingham Palace in December 2022.

Kate, 42, has sported four different tiaras since marrying Prince William in 2011, and the Lotus Flower Tiara was the second (after the Cartier Halo Tiara that she wore for her walk down the aisle to top off her bridal look). She made her debut in the Lotus Flower Tiara in December 2013 for the diplomatic reception at Buckingham Palace and wore it again for her first official state banquet in 2015, welcoming Chinese President Xi Jinping and his wife, Madame Peng Liyuan.

However, the Princess of Wales did not attend the state banquet on June 25 as she remained outside of the spotlight while undergoing chemotherapy. Palace aides emphasized that her appearance at Trooping the Colour on June 15 didn't signal a return to royal duties as she continues cancer treatment.

State visits are an important part of the British royal family’s diplomatic duties, organized to strengthen relationships with other nations around the world. Visiting heads of state are officially hosted by the sovereign, and the busy itinerary includes meetings with government ministers and other organizations. 

The first day of the stay is usually capped with a state banquet, which the royal family's website describes as "a very grand formal occasion" held in the ballroom of Buckingham Palace. Around 150 guests are invited in light of their cultural, diplomatic or economic ties to the country being hosted, and the monarch makes a speech and offers a toast to the visiting head of state, who reciprocates the gesture. 

The glam banquets call for a coordinating dress code, and Queen Camilla glittered in the Ruby Burmese Tiara (which she's worn before) on June 25.

The striking ruby and diamond headpiece that previously belonged to Queen Elizabeth might have been a nod to the hues of the red and white Japanese flag. Women in the royal family often pay homage to countries they are visiting by dressing in national colors.

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The Emperor and Empress of Japan arrived in England on June 22 for a series of private engagements before the state visit officially kicked off on June 25, when Prince William greeted the couple at their London hotel on behalf of King Charles. The King and Queen then greeted Emperor Naruhito and Empress Masako for the traditional ceremonial welcome at Horse Guards Parade, and the visit continues tomorrow with an engagement for Prince Edward and Sophie.

The Duke and Duchess of Edinburgh will join the Emperor and Empress for a banquet at the Guildhall on June 26, organized by the Lord Mayor and City of London Corporation. Edward and Sophie are among the working royals who have continued with a full schedule amid King Charles and Princess Kate's reduced duties when their cancer diagnoses were announced.