Kate Middleton, the future Princess Catherine, debuted her engagement ring at St. James's Palace in London on Tuesday. It's the same ring as Diana, Princess of Wales, wore in 1981. It cost 30,000 at the time and is made from 14 diamonds encircling a sapphire. Kate paired it with a royal blue dress by Issa.

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Take a look at pictures of the ring and of the happy couple. Scroll down for some close-ups.