It is established experimentally that ceramic mixture may be characterized by two threshold values of moisture. The state of a ceramic mixture varies from. In the solid state, the system slides over the contact surface of an anti-body as a whole while in the fluid state, the sliding over an anti-body ceases and the process of sliding replaced by the processes of deformation and the process of flow taking place in the volume of the dispersed system When the values of moisture are intermediate, the mixed regime including both external and internal types of friction takes place. We propose a method for determination of a proportion between external and internal types of friction that allows us to obtain the values of parameters of wall sliding and rheological properties of dispersed systems based on experimental data. It is established that electromotive force due to friction of dispersed systems is depended on the external friction only and thus may be used to estimate the percentage of external friction in the process as a whole.