Abstract: Sedimentation in an inherently colloidally stable mixture comprising a suspension of solids in a liquid is controlled by a five-step process. In the first step a mathematical model representing a relationship between certain parameters, namely area product, viscosity and a parameter related to zeta-potential, is created. In the second step, zones in the model in which there is undesirably high viscosity are identified, In the thrid step, a model sedimentation path which skirts the high viscosity zones is superimposed on the model. In the fourth step, the actual mixture under consideration is monitored during a sedimentation process to obtain actual measured values of any or all of the critical parameters. In the final step, the parameters are adjusted as necessary to fit actual measured values to values on the model sedimentation path.