A gallery in Scotland announced Thursday that it has discovered a previously unknown self-portrait of Vincent Van Gogh, with his ear intact, concealed behind another painting.

The painting was discovered on the back of the canvas of the Dutch post-1885 Impressionist's piece "Head of a Peasant Woman," which had been covered with layers of glue and cardboard.

It depicts a bearded sitter wearing a brimmed hat and a neckerchief tied loosely around his neck. It was finished before Van Gogh severed his left ear in 1888.

Visitors to the National Galleries of Scotland in Edinburgh will be able to see it as an X-ray image through a specially created lightbox at a forthcoming exhibition.

Curators are working on carefully detaching it from the covering canvas without hurting the paintings in the long run.

The National Galleries were "thrilled to bits" by the discovery, according to Lesley Stevenson, the senior paintings conservator.

"When we saw the X-ray for the first time of course we were hugely excited," she said. "This is a significant discovery because it adds to what we already know about Van Gogh's life.

"There is lots to think about with regards to the next steps, but for us it is another little nugget to get us a little bit closer to an incredible artist."

The picture is thought to be part of a series of experimental self-portraits, according to the curators. Five comparable paintings, created before he moved to Paris in 1886, are on exhibit at the Van Gogh Museum in Amsterdam.

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