ARI SHAPIRO, HOST:
It can take a long time to be proven right. The Allentown Art Museum in Pennsylvania was given the painting "Portrait Of A Young Woman" in 1961, and it was told it was the work of the Dutch master Rembrandt van Rijn
MARY LOUISE KELLY, HOST:
But in the 1970s, scholars traveled around the world giving Rembrandts a second look. They eventually came to Allentown.
SHAN KUANG: At that time this painting was demoted.
SHAPIRO: That's conservator Shan Kuang of New York University. She says the painting was declared the work not of Rembrandt but of his assistants. And so it was until the museum recently sent the painting to Kuang for restoration. She says it was coated in a varnish applied in the 1930s to make it as smooth as a mirror.
KUANG: And the previous restorer actually built up layers and layers and layers of varnish to get rid of any surface texture. And in fact, he got so frustrated doing that he eventually ended up pouring a thick varnish onto the surface with the consistency of molasses.
SHAPIRO: She stripped that away, and with all the details in plain sight, some scholars now say that declaration from 50 years ago was wrong.
KELLY: That's right. The Allentown Art Museum has an authentic Rembrandt. The museum's Elaine Mehalakes knows that could change.
ELAINE MEHALAKES: There have been as many as 688 paintings attributed to Rembrandt at one point and as few as 265 attributed to him.
KELLY: Conservator Kuang agrees the Dutch master's work will always draw skepticism.
KUANG: There's something about Rembrandt where it does get a lot more uncertain and political than usual (laughter).
SHAPIRO: The Allentown Art Museum will showcase Rembrandt's "Portrait Of A Young Woman" beginning in June.
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