Bringing new meaning to the idea of stealing someone's heart, thieves in France made off with a 16th-century gold relic containing the once-beating organ of Anne of Brittany, the only woman to ever have been twice crowned the queen of France.

Over the weekend, burglars smashed a window of the Thomas-Dobrée museum in Nantes and lifted the six-inch case from its display, The Telegraph reports.

Anne was crowned queen when she was just 12 years old after marrying Charles VIII of France in 1491. After his death in 1498, she married Louis XII and once again ascended the throne, where she stayed until her death at age 36. Although her body was buried at the Basilica of Saint Denis, she requested that her heart be kept alongside her parents’ tomb in Brittany.

“The thieves attacked our common heritage and stole an item of inestimable value," Philippe Grosvalet, president of the Loire-Atlantique department, which owns the museum, told The Telegraph. "Much more than a symbol, the case containing the heart of Anne of Brittany belongs to our history.”

The gold relic was saved from being melted down after the French Revolution, and it has been kept safe at the Thomas-Dobrée museum for more than 130 years. The case contains an inscription in old French, which translates to: “In this small vessel of pure, fine gold rests the greatest heart of any woman in the world.”

This practice of burying the heart apart from the rest of the body was not entirely uncommon among European aristocrats in the Middle Ages. The hearts of both Richard I and Anne Boleyn were kept in lead boxes, and the hearts of 22 former popes are stored in marble urns at Rome's Santi Vincenzo e Anastasio a Trevi church.

It's also far from the only instance of relic theft. In a slightly more bizarre case, fragments of the brain of John Bosco, a 19th century Roman Catholic priest, were contained in a reliquary at his basilica in Castelnuovo, central Italy, until they were snatched by a thief in 2017. The reliquary was ultimately recovered by police from the suspect’s kitchen cupboard.

[h/t The Telegraph]