Results of the TGMdust model run with iron grains. Left panel: fit to the visibilities with respect to the effective baseline length. The points are color coded for wavelength. The following wavelengths are plotted: 1.7 µm (PIONIER, gray), 2.2 µm (GRAVITY, purple), 3.3 µm (MATISSE L, blue), 4.75 µm (MATISSE M, green), 8.3 µm (orange), 11.3 µm (red), and 12.3 µm (brown, last three are MATISSE N data). Right panel: fit to the SED. The first three data points are 2MASS JHK measurements, the three points between 3 and 5 µm are extracted from our MATISSE LM-band data, and the points between 6 and 18 µm are taken from a Spitɀer observation, except the N band where the points are the average of the Spitɀer and our MATISSE single-dish spectra.