This spring in Holland, a curator from the Museum of Fine Arts spotted a 17th-century gold medallion at the famed Maastricht art fair and knew she had to have it. There was just one problem: Nobody could tell her how the precious piece left Germany after World War II. Enter Victoria Reed, the MFA’s curator of provenance. Her job, as the first endowed curator of provenance at an American museum, is to research works with questionable histories both in the collection and on the MFA’s shopping list. As a result, Reed’s other job is to break curators’ hearts.