It's likely to be Meghan's only tiara moment, given that the Sussexes stepped back as senior royals in 2020.
There have been varying accounts around the royal bride's tiara fitting but Harry has given his version of events in his memoir, Spare, published in January.
The Duke says that he and Meghan were "both touched" when his maternal aunts Lady Jane Fellowes and Lady Sarah McCorquodale asked if the future Duchess would like to wear the late Princess Diana's Spencer
"Shortly before the wedding, however, Granny reached out. She offered us access to her collection of tiaras. She even invited us to Buckingham Palace to try them on. Do come over, I remember her saying," Harry recalls.
"Extraordinary morning. We walked into Granny's private dressing room, right next to her bedroom, a space I'd never been in. Along with Granny was a jewelry expert, an eminent historian who knew the lineage of each stone in the royal collection. Also present was Granny's dresser and confidante, Angela [Kelly]."
Harry says that the late Queen had chosen five tiaras from the vault - "One was all emeralds. One was aquamarines. Each was more dazzlingly stunning than the last".
The royal groom said "each took my breath" but that one of the five that Meghan tried on stood out.
The beautiful art-deco style tiara Meghan wore on her wedding day dates back to 1932.
It features a detachable floral-shaped brooch at its centre, given to the late Queen's grandmother, Queen Mary, as a wedding present in 1893 by the County of Lincoln.
The centrepiece is surrounded by nine smaller diamonds and the bandeau part of the tiara is made up of 11 intricate glittering sections, including ovals and pave set with large and small diamonds.
It came into Elizabeth II's collection when her grandmother Mary died in 1953.
Tiara moments are a rare occasion as they are typically reserved for the bride on her wedding day, state visits, the annual Diplomatic reception and the state opening of Parliament.
The Queen sported the late Queen's Burmese Ruby tiara for the first time while Princess Kate debuted the Strathmore Rose tiara – a delicate floral-themed headpiece that belonged to the Queen Mother.
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