After centuries of mistreatment and nearly 50 years of mystery, a biblical painting in a Dutch museum has finally been declared an authentic Rembrandt. Experts say they needed "CSI-style" tools to authenticate Saul and David, which had been repeatedly over-painted in long-ago restorations and even cut in two at some point in the 19th century, possibly in an attempt to sell it as separate portraits of Saul and David, the New York Times reports.

The Mauritshuis Royal Picture Gallery put the painting on display as a Rembrandt in 1898, but a leading expert cast doubt on its origin in 1969.

A restoration expert tells the AP the skepticism now seems unsurprising because there had been so much paint added there was none of Rembrandt's left to see.

Researcher used tools such as advanced X-ray techniques and paint sample analysis to determine that the Dutch master himself, not one of his followers, created the painting in two stages starting around 1645, the Times reports. Saul and David will now be the centerpiece of an exhibition focusing on the investigation's years of detective work.

"The analysis helped us to determine that the painting is in fact made up of 15 different pieces of canvas; three main parts—the Saul, the David, and an insert of a copy of an old painting in the upper right corner plus strips all around the edges," the museum's director tells the AP.

"So it's a real patchwork." (Another recent art find: Hitler's long-lost bronze horses.)

This article originally appeared on Newser: Mystery of Dismembered Painting Finally Solved

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