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Queen Sofia’s jewelry box is full of Spanish royal treasures, but she also has pieces that come from her own Greek royal family. Today’s jewel is the diamond and ruby pendant she inherited from her mother, Queen Friederike.

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The pendant features a cabochon ruby nestled in a double diamond frame. The frame twists at the top, near where it is connected to a diamond element that allows it to be worn as a pendant. The piece can also be worn separately as a brooch.

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Friederike was a German princess who married King Paul of the Hellenes in the 1930s. Above, she wears the pendant on a pearl necklace during a royal visit to Norway in September 1959.

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The pendant works well with both casual clothing (as shown in the Norwegian visit photo) and more formal attire. Friederike wore the jewel as a brooch for the christening of her son, King Constantine II, in 1940. Almost three decades later, she wore the pendant suspended from a diamond bow brooch for the christening of Constantine’s eldest son, Crown Prince Pavlos, in Athens. You’ll spot the pendant in the photo above on Friederike’s right shoulder.

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The pendant was later inherited by Paul and Friederike’s elder daughter, Sofia, who married the future King Juan Carlos of Spain in 1962. She has worn the pendant often, especially over the last decade or so. Above, she sports it on a single strand of pearls at a dinner given for the President of Hungary in 2009.

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She also, on occasion, wears the pendant with a double strand of pearls. Above, she styles the pendant that way for a church service to celebrate the 70th birthday of King Carl XVI Gustaf of Sweden in April 2016.

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She wears the pendant with all sorts of attire, from dark colors to light, and solid colors to patterns, like the outfit she paired with the jewel for a gala in September 2017.

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The ruby red gemstone is also a handy jewel to have when you’re a member of the Spanish royal family, as Spain’s flag is red and gold. She’s used the pendant to echo the national colors on more than one occasion. In June 2014, she paired her rubies with a pale gold dress at the parliamentary ceremony during which her son, Felipe, was proclaimed King of Spain.

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She also wore the pendant for another major Spanish historical milestone in December 2018: the 40th anniversary of the Spanish constitution, which established democracy in the country.

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But she’s also brought out the pendant for Greek royal celebrations, too. In March 2014, she wore the pendant in Athens for services commemorating the 50th anniversary of the death of her father, King Paul.