0148 GMT May 23, 2022
The antique mirror had been hanging in the family's bathroom for 40 years, while they remained oblivious to its true value, reported the Daily Mail.
The small mirror — which measures about 19 inches by 15 inches — is now expected to fetch at least £8,000 at an auction in Bristol, the UK.
The antique 18th century French mirror glass is mounted in a later 19th century fine walnut carved frame, according to East Bristol Auctions. An engraved silver plaque on the frame reads "This Glass Formerly Belonged To - Marie Antoinette - And Was Purchased At The Sale Of Napoleon's Effects."
It is believed that the mirror was purchased by Napoleon III's wife, Empress Eugenie, who purchased several items from Marie Antoinette's estate.
According to Fox News, a family member inherited the mirror from their grandmother and kept it hanging in their bathroom, not realizing its true worth. The plaque, they thought, was only a joke.
Aiden Khan of East Bristol Auctions said: "It's remarkable to think this mirror, with its incredible history, has been sat on a wall of a downstairs loo for so long.
"It's a real piece of history — a tangible link to one of the most famous figures of the eighteenth century."
Marie Antoinette was the last queen of France, married to Louis XVI. She reigned between 1774 and 1792. She was executed during the French Revolution.