The Princess of Wales wearing the Festoon Necklace, which belonged to the late Queen Elizabeth II.

Lady Ogilvy, and the Duke of Edinburgh.

Queen Elizabeth II wearing the Festoon Necklace at a state banquet in Stockholm.

Official Portraits Reveal Kate Middletons Hidden Tribute to the Late Queen on Coronation Day

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Queen Elizabeth II at the State Opening of Parliament on November 6, 2007.

Queen Elizabeth II at the State Opening of Parliament in Melbourne, Australia.

in February 1954, one of the first times she was seen wearing the necklace after becoming queen.

The Princess of Wales wearing the Festoon Necklace which belonged to the late Queen Elizabeth II.

The Princess of Wales wearing the Festoon Necklace, which belonged to the late Queen Elizabeth II.

Diana was photographed wearing them numerous times, including on a visit to Australia in 1996.

This article first appeared onBritish Vogue.

From left The Duke of Kent the Duchess of Gloucester the Duke of Gloucester Vice Admiral Sir Tim Laurence the Princess…

From left: The Duke of Kent, the Duchess of Gloucester, the Duke of Gloucester, Vice Admiral Sir Tim Laurence, the Princess Royal, King Charles III, Queen Camilla, the Prince of Wales, the Princess of Wales, the Duchess of Edinburgh, Princess Alexandra, the Hon. Lady Ogilvy, and the Duke of Edinburgh.

Queen Elizabeth wearing the sentimental necklace on a state visit to the US at a party hosted by first lady Nancy Reagan…

Queen Elizabeth wearing the sentimental necklace on a state visit to the US at a party hosted by first lady Nancy Reagan in Hollywood in February 1983.

Queen Elizabeth II wearing the Festoon Necklace at a state banquet in Stockholm.

Queen Elizabeth II wearing the Festoon Necklace at a state banquet in Stockholm.

Queen Elizabeth II at the State Opening of Parliament on November 6 2007.

Queen Elizabeth II at the State Opening of Parliament on November 6, 2007.

Queen Elizabeth II at the State Opening of Parliament in Melbourne Australia. in February 1954 one of the first times…

Queen Elizabeth II at the State Opening of Parliament in Melbourne, Australia. in February 1954, one of the first times she was seen wearing the necklace after becoming queen.