The normalised flux (πF_n) and degree of polarisation (P_s) of starlight reflected by a planet covered by two cloud layers; the lower (upper) one composed of model particles B (A). The top of the upper cloud is at 0.628 bar, and for these calculations, the cloud layers themselves do not contain any gas molecules. The lines pertain to different combinations of cloud optical thicknesses (at 0.55 microns): upper cloud b₂ = 0.5, lower cloud b₁ = 1.5 (orange, dashed-tripple-dotted line); upper cloud b₂ = 1.0, lower cloud b₁ = 1.0 (black, solid line); upper cloud b₂ = 1.5, lower cloud b₁ = 0.5 (green, long-dashed line). For comparison, we also included the cases in which both cloud layers contain particles B with total b₁ = 2.0 (red, dashed line), and particles A with total b₂ = 2.0 (blue, dashed-dotted line).