BBC Press Office

Tonight, the Queen will give a rare interview in a new documentary about British coronations. (You can read more about the documentary over here!) Along with an appearance by St. Edward’s Crown, which rarely leaves the Tower of London, the documentary will also include an outing for one of the Queen’s lesser-worn brooches, the magnificent Cullinan III and IV Brooch.

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The brooch is made of the third and fourth largest stones cut from the famous Cullinan Diamond. The enormous 3,106 carat uncut diamond was presented to King Edward VII in 1907, and it was cut by Joseph Asscher in Amsterdam the next year. The largest two stones sourced from the diamond are now set in the Sovereign’s Scepter and the Imperial State Crown. The pear-shaped Cullinan III (weighing 94.4 carats) and the square-cut Cullinan IV (weighing 63.6 carats) were among the stones purchased from the Asschers after the cutting and polishing process by the South African government. (Hugh Roberts notes that the Asschers had retained the lion’s share of the smaller Cullinan diamonds, calling them the “chippings,” as “the fee for cutting and polishing the Cullinan.”) The government then presented the diamonds to Queen Mary in 1910.

Grand Ladies Site

Queen Mary, as always, was innovative in her use of the diamonds. In 1911, she commissioned Carrington and Co. to make a platinum brooch setting for the stones. Above, you can see the brooch pinned to the bodice of her dress.

Grand Ladies Site

For King George V’s first state opening of parliament in 1911, Mary went all out, wearing the Cullinan I and II stones together as a humongous brooch (pinned near her Garter sash in the portrait above) and using the Cullinan III and IV stones as a pendant on one of her many diamond necklaces.

She even wore the Cullinan III and IV on the grand Delhi Durbar Tiara. The Cullinan IV is set in the center of the tiara, while the Cullinan III is placed upright at the top of the piece. (She’s also wearing even more Cullinan stones on her bodice, set in brooch form, in this portrait.)

The Queen inherited the brooches from her grandmother in 1953. She hasn’t worn it often, probably because it’s one of the most ostentatious brooches in her entire collection. But it was an especially appropriate choice for the state visit to the Netherlands in 1958. Above, she wears the brooch on a trip with the Dutch royal family to the Asscher workshop in Amsterdam, reuniting the brooch briefly with the firm who created its magnificent diamonds.

She also loaned it to the Ageless Diamond exhibition, held in London in 1959. (More on that over here!)

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The brooch was also part of the incredible diamond exhibition at Buckingham Palace in honor of the Queen’s Diamond Jubilee in 2012. Above, Caroline de Guitaut, Curator of the Royal Collection, holds the brooch, giving a good idea of its scale. You can also see the additional pendant loop at the top of the brooch in this photograph.

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Of course, the brooch was also an obvious choice for the service of thanksgiving at St. Paul’s Cathedral during the Queen’s Diamond Jubilee summer in 2012. Nothing says “I’ve reigned for 60 years” like two of the biggest diamonds in her private collection!

Where does this brooch fall in your rankings of the Queen’s diamonds?