For her first state trip of the year, Queen Mary of Denmark has selected some of the most special jewelry in her collection. On Tuesday night, for the gala banquet held in honor of her visit by the Estonian president Alar Karis, Mary paired a 2015 Prada dress with the diamond tiara she wore on her wedding day to King Frederik. The second stop of their trip arrived when the King and Queen of Denmark attended a state dinner in Lithuania. For the evening, Mary of Denmark donned a dress by Elie Saab, a designer that is new to the closet of the Australia-born monarch.

The burgundy gown, adorned with a cape and lengthy sleeves, was accessorized with a very special tiara—one that Queen Mary of Denmark bought herself at a 2012 auction. This necklace, which can also be worn as a tiara, dates back to the early nineteenth century and is composed of diamonds, rubies and spinels, mounted on a gold and silver structure.

Mary acquired it, along with matching earrings—which she also wore for the dinner—from auction house Bruun Rasmussen when she was still a crown princess, according to reports. The set had a starting price of between €4,000 and €5,350, although the queen is said to have paid almost double that. Mary of Denmark had to make some repairs to the piece, including adding some missing gemstones. She didn’t debut the necklace until three years later, when she wore it for Queen Margrethe’s 75th birthday concert.

Mary de Dinamarca

Mary of Denmark at Queen Margrethe’s 75th birthday in 2015, wearing the necklace-turned-tiara.

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