A painting bought at a garage sale in Minnesota is a previously unknown portrait by Dutch artist Vincent Van Gogh, according to a newly published expert analysis.

During Vincent van Gogh’s year-long stay in a French asylum, he created some 150 paintings—including Irises and The Starry Night. He also painted many interpretations of other artists’ work, calling them “translations.

The global art mystery began at a garage sale in Minnesota after a simple painting that could be worth millions was bought.