Duchess Kate wore her signature Lover's Knot tiara.
Tonight, Queen Elizabeth is hosting an evening reception for members of the Diplomatic Corps at Buckingham Palace in London. The glitzy annual affair was attended by numerous members of the royal family, including Prince William and Kate Middleton. The royals were decked out in white-tie ensembles, and a few sparkling tiaras made an appearance as well. See every photo from the evening here: