Aq. 35% (by vol.) coating colors were prepd. with a mineral pigment (kaolin, natural CaCO3 or TiO2) and a styrene-butadiene latex (SBL). The pigment vol. concn. (PVC) was varied from 20 to 95% at 5 or 10% steps. The coating colors were applied on basestock by using a draw-down coater (K bar No. 3) to yield 24-mu m wet coatings. The coated paper was IR-dried and stored at 23 +/- 1 degrees C and 50 +/- 2% RH. The hiding power was detd. from the light scattering coeff. calcd. from Kubelka-Munk's theory. As PVC was raised, the hiding power rose. It was max in TiO2 coatings. It fell in the order TiO2 > CaCO3 > kaolin. Hiding-power changes were attributed to (i) dry coating porosity, (ii) pigment particle shape (rhomboidal CaCO3 vs. clay platelets), and (iii) pigment refractive index.