A painting of French King Henri III (1551–89) that was stolen from the Louvre museum in Paris more than six decades ago during World War II will be returned  to the museum, according to a report in The Art Newspaper, after a vigilant curator noticed that it was set to be auctioned in Paris.

Pierre-Gilles Girault, assistant curator at the Château Royal de Blois in the Loire Valley, received an email alert that the work was set to be sold at Drouot auction house Ader-Nordmann this past Friday, October 17. Girault recognized the small portrait, which shows Henri III at prayer beneath Christ on the cross. Girault, who curated a 2010 exhibition focused on Henri III (“Renaissance Celebrations and Crimes, the Court of Henri III”), knew that the work had formerly been in the collection of the Louvre but that it had disappeared during the war and there was no further information about it.

Girault assumed that the work, which was estimated at $510–760 (€400–600) was a copy, but the Louvre identified it as the missing original after examining it. According to the report, the painting is “an important piece of royal iconography,” that focuses on the king’s piety as opposed to a scene from court life. The work was removed from the sale and will be returned to the Louvre. The report says there have been calls for the Louvre to loan the work to the Chateau de Blois as a sign of gratitude for the curator’s find.