Friday marks a somber anniversary for the University of Arizona Museum of Art.
The painting was Woman Ochre by the abstract expressionist master Willem de Kooning. Museum officials estimate that today it could be worth up to $160 million dollars.
Curator Olivia Miller said that figure is based on how much de Kooning’s paintings have been selling for at auction, but in a way, its monetary value is meaningless.
"As a museum we would never sell the painting, it’s here for the public good," she said.
Unfortunately though, it’s not there. What happened to Woman Ochre remains a mystery and the investigation is ongoing.
The museum sometimes puts what’s left of the work on display: an empty frame with the frayed edges of one of the most valuable paintings of the 20th century.
Watch a version of this story that aired on Arizona Illustrated