After assessing two paintings in its collection attributed to 17th century Dutch painter Johannes Vermeer, the National Gallery of Art in Washington will officially change the attribution of one of the paintings, Girl With a Flute, on Saturday after determining that Vermeer did not actually paint it, The New York Times reports. While the confirmed Vermeer painting Girl With the Red Hat and Girl With a Flute appear to have the same subject, the non-Vermeer lacks the even surface the artist’s canvases were known for, conservators and scientists determined. “We know nothing about who created this and under what circumstances,” Marjorie E. Wieseman, who leads the National Gallery’s Northern European paintings department, told the Times.