Madrid (CNN) -- The Prado Museum put on display for public viewing Tuesday a restored version of what is thought to be the earliest known copy of Leonardo da Vinci's "Mona Lisa" masterpiece, which hangs in the Louvre Museum in Paris. Many copies of "Mona Lisa" were painted years after the fact, but this copy is different, experts say, because evidence shows it was painted at the same time and in the same studio as the original masterpiece, probably by one of Leonardo's assistants or pupils. The copy shows the same woman and the same landscape, the Prado Museum said in a statement.
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The painting is believed to be the earliest known copy of the "Mona Lisa"
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Evidence shows it was painted at the same time and in the same studio as the original
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The background was painted over with black during the 18th century
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The restored copy has background details linking it more closely to the original
At a packed news conference at the museum, @placeholder officials said the "Mona Lisa" copy underwent a big change in the 18th century, when someone ordered the colorful background landscape to be painted over in black.