Evolution of a representative pebble at 1.8 au, nucleating when S = 2, corresponding to a time of t ≈ 840 yr. Panel a shows the super-saturation S at 1.8 au. Panel b shows the particle size in metres and Stokes number. We mark St = 0.01 with a dotted line. Panel c shows the growth rate in millimetres per year, and panel d shows the sedimentation and growth timescales. The cooling time of the disc is t_cool =100 yr.