Known as the Lotus Flower Tiara, the crown jewel that Palace insiders say was loaned to the Duchess of Cambridge by Queen Elizabeth from her collection dates back to the Queen's mother in the 1920s.
"It's a beautiful pearl and diamond piece," expert Leslie Field, author of The Queen's Jewels, says about the Egyptian-style tiara, which was also previously owned and worn by the Queen's late sister, Princess Margaret. "It's very much in the '20s style and probably quite lightweight and comfortable to wear."
Popperfoto / Getty
Kate, 31, wore a tiara for only the second time since her 2011 wedding to Prince William, dazzling onlookers in the jewels and a white Alexander McQueen dress as she arrived in a chauffeur-driven Bentley to help the Queen entertain diplomats at the annual state reception.
Speaight / Mansell / Time Life Pictures / Getty
The tiara's history doesn't stop there – it was handed down by the Queen Mother to her second daughter, Margaret, who lent it to her daughter-in-law Serena Linley to wear on her 1993 wedding day.