Dust mass vs. stellar mass in different redshift ranges. Symbols are colour coded according to their SFR, as shown by the colour bar. At each M_star, black open circles mark the bin which lies closest to the MS (in each M_star interval), and in every case within 0.3 dex from it. The correlations between M_dust and M_star are rather flat when the data points are separated by means of their SFR. The dashed lines correspond to an amount of dust equal to the maximum metal mass , where y_Z ~ 0.014, assuming the extreme case of a condensation efficiency of 100%, while the dotted line shows the case when only 50% of the metals are depleted into dust grains (see text).