Art historians say a "lost" Leonardo da Vinci masterpiece may be hidden behind a fresco in Florence’s Palazzo Vecchio, that has not been seen in over four centuries.
Da Vinci’s “The Battle of Anghiari” is said to be preserved on a wall behind Giorgio Vasari’s “The Battle of Marciano," wrote the BBC.
Last year, researchers drilled tiny holes into Vasari's fresco, according to the Guardian, and after chemical analysis found that the existing mural had found black pigment also used in the “Mona Lisa."
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But Agence France Presse reported that historians at a press conference on Monday in Florence stressed their research was "not conclusive." The project remains controversial.
"We need the courage to push on and resolve this mystery," said Matteo Renzi, the mayor of Florence, who is urging the Italian government to approve removal of parts of The Battle of Marciano in Val di Chiana, which was painted in 1563, and is a famous work for art in it's own right.
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Da Vinci worked in the Hall of Five Hundred in the Palazzo Vecchio but in 1504 completed only the centrepiece of his work. This was later copied by Rubens, whose drawing hangs in the Louvre. After 1555, the palace room was renovated and Da Vinci's half-finished painting was believed lost forever.