Duchess Kate wears Princess Diana's Cambridge Lover's Knot tiara for palace reception

/ Source: TODAY

Duchess Kate channeled the people's princess for one of Buckingham Palace's biggest receptions of the year.

The Duchess of Cambridge donned Princess Diana's signature tiara, the Cambridge Lover's Knot Tiara, for the palace's annual Diplomatic Reception Tuesday night.

Catherine, Duchess of Cambridge, attends the annual Diplomatic Reception at Buckingham Palace on December 8, 2015 in London, England.Julian Parker / Getty Images Contributor

She completed the look with a re-used ice blue Alexander McQueen gown (one that Duchess Kate wore to the same reception in 2013). Tuesday marked only the fourth time Duchess Kate has worn a tiara, and the first time she has worn Diana's headpiece.

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The Cambridge Lover's Knot tiara was a wedding gift to Diana from Queen Elizabeth in 1981, and Diana wore the royal jewels regularly until she gave the tiara back after her divorce from Prince Charles.

Originally commissioned by Queen Mary around 1913, the tiara features 19 drop-shaped pearls that hang from diamond arches topped with diamond bows. The large hanging pearls reportedly make the tiara heavy and difficult to wear and gave Princess Diana headaches, so she often opted to wear her family's Spencer tiara.

Catherine, Duchess of Cambridge and Prince William, Duke of Cambridge attend the Diplomatic Reception at Buckingham Palace on December 8, 2015 in London, England.Mark Cuthbert / Getty Images Contributor

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The Diplomatic Reception was just the start of a few scheduled appearances for Duchess Kate and Prince William.

On Wednesday morning, the royal couple stopped by global brokerage firm ICAP's trading floor for the company's annual charity day, during which the firm donates all of its daily profits to charity.

During their visit, Will and Kate "closed deals" on the trading floor as well as played ping pong and some office-friendly basketball.

Britain's Catherine, Duchess of Cambridge, arrives for a charity event at city company ICAP, in central London, Britain December 9, 2015. REUTERS/Toby Melville Toby Melville / Reuters