Is a painting in storage at Yale University Art Gallery an early work by Diego Velazquez?

Curators often rummage through museum storage hoping to find a great painting or just a curiosity overlooked by their predecessors. But it’s not every day that they find a canvas that they identify as an early masterpiece by Diego Velázquez, as John Marciari has.

Marciari, now curator of European paintings at the San Diego Museum of Art, has published an article in the new issue of the Madrid quarterly Ars making the case that an unidentified painting in storage at the Yale University Art Gallery is actually an altarpiece by the Spanish master. The journal says the Yale work “could be this master’s most significant find for more than a century.”

At the Yale gallery, the curator of early European art Laurence Kanter calls the discovery all the more remarkable because museums today so rarely have the chance to acquire a work by Velázquez, an enormously influential narrative and portrait painter who was already celebrated and collected in his lifetime.

As Kanter points out, Velázquez “has never been out of favor. From the beginning, he has been one of the great, canonical painters of the Western tradition, and because he worked for the kings of Spain, most of his work is still in that country.”

Correction: An earlier version of the caption for the Velasquez painting gave an incorrect year it is believed to have been made. The correct year is 1617.

More than 5 feet by 4 feet, “The Education of the Virgin” shows the young Virgin Mary learning how to read at the hands of her mother, St. Anne, with her father, St. Joachim, looking on. Given to Yale in the 1920s by alumni Henry Hotchkiss Townshend and his brother Raynham, the oil on canvas was previously listed as the work of an unknown 17th century Spanish painter.

Marciari first saw it in early 2004, when he was a junior curator at the Yale gallery working for Kanter. They were going through new storage facilities, with an eye toward reinstalling the galleries.

“The Education of the Virgin,” missing paint in spots and trimmed at the top, looked “pretty beat up,” Marciari says. “It was dirty, with a bit of tissue paper stuck on the canvas to hold the paint in place. This is how you find paintings in storerooms everywhere.”

But even then, he said, the painting stood out, much as the figures themselves emerge dramatically from darkness. “I definitely thought it was a compelling painting. But it wasn’t until a few months later, when I pulled out the painting again, that it hit me: This is an early Velázquez.”

He said it was like combing through a catalog of images in his mind, until something clicked.

“This is how connoisseurship works,” he says, “It’s not so different than a doctor looking at a group of symptoms and identifying a disease.”

He spent time over the following years marshalling stylistic evidence and technical data to support his hunch. He found comparable elements, such as St. Anne’s ochre-colored draperies and St. Joachim’s basket, in accepted Velázquez works.

He did technical analysis and found the canvas and pigments consistent with what we know about Velázquez, down to the way the artist combined azure blue and yellow ochre to make green. And Marciari worked with a conservator at Yale to take X-rays of the image.

“Technology much more often disproves than proves an attribution,” but X-rays help, he says, to reveal the history of revisions. Or, in this case, the confidence of the brushwork.

“One of the things evident in these X-rays is that the paint in the draperies is applied with long confident strokes, no hesitation, no sense of an artist trying to figure things out, even though Velázquez would have been 18 at the time,” Marciari says. He believes “The Education of the Virgin” was painted in 1617.

Marciari even developed a theory about the original location of the painting, which appears to have suffered water damage. He imagines that it was the altarpiece at the Carmelite Convent of St. Anne in Seville, Spain, which flooded in 1626.

Although he has presented his proposed reattribution in lectures over the last few years, the news did not make headlines until last week, after the editors of Ars alerted local media and the newspaper El Pais ran the story on its front page.

Although most scholars reserve judgment until they have seen the painting themselves, a few have already expressed enthusiasm. Most notably, talking to El Pais, Benito Navarrete, director of the Velázquez Center in Seville, called it a “very important painting” that was “essential in the formation of early Velázquez.”

Antonio Bonet Correa, director of the Royal Academy of Fine Arts of San Fernando in Madrid, proposed an international conference to discuss this attribution, among others. Curators at the Prado Museum, the mother lode of Velázquez paintings, have not publicly weighed in.

Marciari says he’s “thrilled” with the response so far, especially considering that there’s “a natural degree of skepticism to news that someone has found a Velázquez.”

This skepticism stems in part from the fact that a reattribution dramatically boosts a work’s value in the annals of art history and in the marketplace. The difference between an unidentified work from Seville and a Velázquez — even a damaged Velázquez — can easily amount to several million dollars.

But Kanter at Yale says its financial value is beside the point: “The picture will never be for sale — it’s our obligation to preserve it for posterity, not to cash in on it.” He hopes to put the painting on display within a couple of years, once it has been restored.

Before then, Kanter’s goal is “to invite as many people as possible to examine it in person, not only to assemble a critical mass of opinion but to understand the direction we need to pursue for restoration.” He imagines creating a study day for a team from the Prado.

Meanwhile, at the San Diego Museum of Art, which he joined in 2008, Marciari has another set of mysteries to solve. Part of his mission when he was hired from Yale was to catalog the museum’s Old Masters paintings, which have received little scholarly attention.

“It’s essentially the same kind of work: doing provenance research, technical studies, fitting works in the career of one or another artists,” he says.

There might be some reattributions to come, he adds, but nothing of this stature. “There’s no Velázquez in the basement,” Marciari says.

jori.finkel@latimes.com