Two paintings at the Mauritshuis museum in The Hague that were long attributed to Rembrandt were not painted by the master himself, the museum said during a presentation on Thursday.

Experts recently examined three paintings from the museum’s collection and concluded that two of them may have been created in Rembrandt’s studio, rather than by Rembrandt’s own hand.

“Rembrandt research is never done, and that includes the work we do at the Mauritshuis,” the museum said in a statement.

Study of an Old Man (c. 1655–1660), which bears Rembrandt’s signature, was found to be the work of someone employed by him. The signature was applied while the paint was still wet, and the handwriting is definitely Rembrandt’s, the museum said.

However, the painting appears “awkward”, as if a student had done their best to imitate the master. In the 17th century, it was not unusual for a master to sign a student’s work to help it sell.

The second work, Portrait of Rembrandt with a Gorget (c. 1629), has not been considered an original Rembrandt for the past 25 years. It has now been confirmed as a copy of another work by someone from his studio.

The third painting, Tronie of an Old Man (c. 1630), is painted on a wooden panel from the same tree used for two known Rembrandts. This makes it “highly likely” that it was produced in his studio, the museum said.

“The brushwork is somewhat coarse, the red highlights in the man’s eye are not typical of ‘real’ Rembrandts, and the brushstrokes are imprecise,” the museum said. “But there are high-quality elements, such as the convincing way the cap sits on the man’s head.”

The work could have been painted by a student, an assistant, or Rembrandt himself — and the mystery remains unsolved. All three paintings are now on display as part of a special exhibition at the Mauritshuis.