Researchers in Florence, Italy believe they have struck art gold—an unfinished fresco by Renaissance master Leonardo da Vinci.

Dubbed the "Lost Leonardo", its remnants were discovered behind a wall containing a fresco by 16th century artist Giorgio Vasari. And though not everyone agrees, National Geographic's Terry Garcia is sure that the hidden painting is a da Vinci.

The Executive Vice President says, "There is overwhelming historical documentation that indicates the Leonardo was painted, it was behind the wall and it was in existence at the time that Vasari painted his fresco."

Apparently da Vinci abandoned his project a year after starting. And it's thought that when Vasari started his fresco, he loathed to paint over the master's work and so built a wall several centimeters in front of the original.

Historians believe he left a clue in his battle scene in the form of the words, "Cerca e trova" which mean "Seek and you shall find".

Art diagnostics expert Maurizio Seracini says he also found traces of pigments used exclusively by Leonardo, leaving no doubt about the fresco's authenticity. He says, "Having found these pigments, having found organic material as well, cannot be just a coincidence."

New video technology will ensure that the public can view the hidden fresco—even if it's unclear whether it is the "Lost Leonardo".