Kate Middleton, Now in Princess Diana’s Tiara

ALERT: Kate Middleton is not wearing royal blue. She is not wearing pastel coats, nor is she is wearing her most somber outfit of the year. She's definitely not wearing athleisure. No, Kate Middleton, is wearing her most beautiful and important accessory yet: the tiara of her husband's late mother, the beloved Princess Diana.

While en route to the Diplomatic Reception at Buckingham Palace with Prince William, Kate wore a diamond- and pearl-encrusted tiara. Lest you assume a princess wearing a tiara is hardly newsworth, it's actually only one of four times in history— including Kate Middleton's marriage to Prince William — that she's ever worn one.

The Daily Mail reports the tiara in question is the Cambridge Lover's Knot tiara, given to Princess Diana in 1981 by Queen Elizabeth. Its history, however, stems back to 1914, when it was made by Queen Mary, who copied the design from her grandmother. Queen Elizabeth, too, wore it back in 1955. Here's a closer look at it:

And here's Princess Diana wearing the very same tiara in 1983:

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