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As Valentine weekend draws to a close, today we’ve got a look at an appropriately named royal jewel: Queen Mary’s Lover’s Knot Brooch.

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The imposing bow brooch dates to the end of the nineteenth century. It wasn’t a royal commission; instead, it was acquired by Queen Mary from Garrard in 1932. In the portrait above, painted in April 1934 by Sir Oswald Birley, Mary wears the brooch with her diamond sautoir, diamond earrings, and the diamond choker necklace now worn as a bracelet by the Duchess of Cambridge.

The Queen inherited the brooch from Queen Mary in 1953. She’s worn the piece consistently throughout her reign, often for significant family and diplomatic events. In April 1960, she wore the brooch with the Diamond Diadem and her sapphires at Covent Garden during the state visit of President DeGaulle of France.

A month later, she wore the brooch with pearls for the wedding of her sister, Princess Margaret, at Westminster Abbey.

The brooch was a favorite jewel of the Queen in 1960 — she also chose it for that year’s Christmas Message.

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In December 1961, the Queen wore the brooch with pearls and the Girls of Great Britain and Ireland Tiara to watch a performance by local dancers during a visit the Northern Province of Sierra Leone.

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The size of the brooch, as well as its immense sparkle, make it especially appropriate for securing order sashes during white-tie events. In May 1972, she paired the brooch with Queen Alexandra’s Kokoshnik and the Baring Ruby Necklace for dinner with President Pompidou of France at the British Embassy in Paris.

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The brooch was worn to honor another French president in October 1984, when the Queen wore it with the Girls of Great Britain and Ireland Tiara and the Godman Necklace for a dinner in honor of President Mitterrand at the French embassy in London.

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The diamond brooch dazzled in May 1998 for a state banquet at Buckingham Palace in honor of Emperor Akihito of Japan. On that occasion, the Queen wore the brooch with Queen Alexandra’s Kokoshnik and the Coronation Necklace and Earrings.

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The Coronation Diamonds made another appearance with the brooch in June 2001, when the Queen honored President Mbeki of South Africa with a state banquet at Windsor Castle. On that occasion, she also wore the widowed setting of the Vladimir Tiara.

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In May 2007, she wore the brooch with the Girls of Great Britain and Ireland Tiara, her diamond frame earrings, and her diamond festoon necklace for a state dinner at the White House in Washington, D.C.

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One of the most important appearances of the brooch in recent memory came in April 2011, when the Queen wore it for the marriage of her grandson, the Duke of Cambridge, to Kate Middleton at Westminster Abbey. The lover’s knot motif is always a perfect choice for a wedding!