The Greville Emerald Kokoshnik Tiara

This is a tiara originally owned by Dame Margaret Greville, who left her jewelry to the Queen Mother in her will.

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Neither the Queen Mother or Elizabeth II were seen in it in public. The first time a member of the Royal Family wore it was in 2018, when Princess Eugenie wore it on her wedding day. More recently, Queen Camilla wore it in 2025 at a reception at Windsor Castle.

It was made by renowned French jewellers Boucheron, in 1921, and mixes an art-deco style with the Russian kokoshnik (cockscomb) shape. It features nine cabochon emeralds set amidst diamonds, with platinum holding the design in place.

Here's looking forward to seeing Princess Catherine wearing it.