Queen Elizabeth II is celebrating her diamond anniversary on the throne this year—her 60th!—and kicked off celebrations at St. Paul’s Cathedral in London last night. Fittingly, she wore lots of diamonds for the service, including one of her favorite tiaras, known as the “Girls of Great Britain.” The silver crown is an heirloom, as it was a present to Queen Mary on her wedding day from the Girls of Great Britain and Ireland, hence its name, and was creatively designed so it could also be worn as a necklace. (What a necklace that would be!) The piece will be going on display as part of the “Diamonds: A Jubilee Celebration” exhibition of Queen Elizabeth’s most famous jewels, which opens at Buckingham Palace this summer. For tickets, visit rceltickets.com.

Plus, see Catherine, Duchess of Cambridge’s best outfits.

KATE'S BEST OUTFITS!

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