Kate Middleton Just Wore Queen Elizabeth's Favorite Pearl Necklace

Kate Middleton is continuing to pay tribute to Queen Elizabeth with her "mourning" jewelry. 

After wearing the monarch's pearl and diamond drop earrings on four separate occasions this week, as well as one of her brooches at Westminster Hall, the newly-appointed Princess of Wales stepped out in arguably the most significant piece from the queen's collection over the weekend. 

On Saturday, Kate joined her husband Prince William and other members of the royal family for a lunch reception at Buckingham Palace, where she met with governors-general of the Commonwealth nations who traveled to London for the late royal's funeral. At the event, Kate wore a long black dress with matching tights and pointed-toe pumps, and complemented her dress's high neckline with a three-strand pearl necklace previously owned by Queen Elizabeth. 

The necklace was the queen's signature accessory — she was rarely spotted without it. 

In fact, she reportedly wore the necklace daily, according to her former assistant private secretary, Sam Cohen. "She wasn't interested in material things at all," he told People, adding: "She wore the same pearl necklace every day."

More pearl jewelry will likely be spotted at the queen's funeral on Monday. Pearls became associated with royal mourning after Queen Victoria wore black clothing with the colorless gems following her husband Prince Albert's death in 1861. Queen Elizabeth kept the tradition going when her father King George VI passed away, as well as at the funerals of her sister Princess Margaret and her former daughter-in-law Princess Diana.