Kate Middleton
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Every princess needs the perfect tiara. And for Duchess of Cambridge Kate Middleton hers comes borrowed from Princess Diana—because when you're part of the royal family, you get your pick of the best jewels.

At a recent state banquet for visiting royalty King Felipe VI and Queen Letizia of Spain, Middleton wore a stunning pink lace Marchesa dress, a statement necklace borrowed for the night from the Queen, and a very special tiara. The diamond and pearl Cambridge Lover’s Knot tiara, as Vanity Fair notes, was a wedding gift to Princess Diana and known to be one of Diana's favorite pieces.

The tiara is a historical treasure and is a little more than a century old, according to People, and was commissioned by Queen Mary sometime in 1913 or 1914. It has 19 arches, and a total of 38 drop-shaped pearls.

Anwar Hussein

The first time the Duchess of Cambridge wore the special tiara was at a state banquet in 2015, according to People—and this year's celebration is the second time she's worn it since, so it seems like it has quickly become a favorite of hers as well. Custom dictates that only certain occasions allow for a tiara, and as the largest event Buckingham Palace throws each year—this year, with more than one thousand people from 130 different countries, VF reports—a state banquet definitely qualifies.

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