Abstract: Rank-correlation coefficients are utilized to show relationships between physical and chemical properties of Georgia and English kaolins. Montmorillonite impurity in the Cretaceous kaolins shows high level correlations with magnesium, iron, silica-alumina ratio, CEC, water sorption, surface area, sediment volume, and Brookfield viscosity. Cation exchange capacity of these kaolins is believed to be related primarily to montmorillonite impurity. Low shear viscosity measurements show a strong correlation to properties indicative of montmorillonite. Correlations with viscosity are believed to be related primarily to surface area and particle packing. Packing volume exerts a dominant effect on high shear rheology. Differences in particle shape are not of sufficient magnitude to show a significant effect on rheology. A strong inverse relationship of vanadium with high shear viscosity indicates that the wetting effect of vanadium organic complexes or adsorption of (VO4)−3 tetrahedra at gibbsite edge faces may be mechanisms for viscosity reduction. Brightness and whiteness are related to titanium and iron-bearing impurities as well as the amount of particles having optimum diameters for light scattering. Well-crystallized kaolinites are believed to have been derived primarily from feldspar. Muscovite alteration may be retarded where well-crystallized kaolinites occur. To account for the inverse relation of vanadium with crystallinity, it is suggested that complex vanadium ions may act as growth poisons.