French amateur astronomer Pierre Antonini obtained a lightcurve of Dufour from photometric observations taken during April 2010.
According to the surveys carried out by the Infrared Astronomical Satellite IRAS and the Japanese Akari satellite, Dufour measures 50.3 and 51.2 kilometers in diameter and its surface has an albedo of 0.040 and 0.039, respectively [REF].