Degree of processing for the silicate grains in the disks around the IMTT star sample (open circles) and for the HAeBe sample from Juhász et al. (2010) (crosses). Group I disks are black and Group II disks are red. Smaller grains lead to a high peak-over-continuum intensity and a low [F_11.3 ∕F_9.8] ratio. As grains grow, the [F_11.3∕F_9.8] ratio increases and the peak-over-continuum intensity weakens.