Princess Diana
Princess Diana was unable to keep the Cambridge Lovers' Knot tiara after her divorce from Prince Charles. Pictured: Princess Diana is seen during the official Madame Tussauds' wax effigy of HRH Prince William is unveiled at London's Marylebone Road tourist attraction on August 3, 2005 in London, England. Getty Images/MJ Kim

Princess Diana was allowed to keep the majority of the jewelry she amassed while married to Prince Charles except for one.

According to Reader’s Digest, Princess Diana stunned in the Spencer tiara and the Cambridge Lovers’ Knot tiara. The first one was a family heirloom, and the second one was loaned to her as a wedding gift by Queen Elizabeth II.

However, Princess Diana was unable to wear the Lovers’ Knot tiara later because she and Prince Charles divorced in 1996. The ex-couple’s divorce settlement stated that the Princess of Wales could keep all of the jewelry she used as a royal except for the Cambridge tiara.

Princess Diana was asked to return the headpiece to Her Majesty because it belonged to the royal family’s private collection. The British law also stated that Princess Diana was no longer a member of the royal family, so she was no longer allowed to wear the Lovers’ Knot tiara.

The Cambridge Lovers’ Knot tiara has 19 arches and 38 teardrop-shaped pearls. Queen Mary was actually the one responsible for ensuring that female royals could wear the tiara. The original headpiece was worn by Queen Mary’s grandmother, Princess Augusta of Hesse, the first Duchess of Cambridge.

Since Queen Mary didn’t inherit the tiara herself, she commissioned court jeweler Garrard in 1913 to make her one. The tiara was passed down to her granddaughter Queen Elizabeth II.

The last time that Princess Diana wore the Lovers’ Knot tiara was in 1991, just one year before she and Prince Charles announced their separation. Kate Middleton managed to wear the headpiece four years after she married Prince William when she attended the annual Diplomatic Reception at Buckingham Palace. She also wore the tiara at the same event in 2016.

Middleton wore this tiara when she attended a banquet held in honor of ing Willem-Alexander and Queen Maxima of the Netherlands in October. The mom of three paired the tiara with her teardrop pearl earrings and matching diamond and pearl necklace that once belonged to Queen Mother.