In this paper for to elucidate the mechanism of montmorillonite recharging in the solutions of Cr(NO3)3 and setting up the zones of stability and coagulation of dispersions the dependences of ξ-potential and stability of MMТ dispersions in mentioned solutions on pH medium and concentration of chrome compounds have been studied. With the increase of pH, in the interval of pH meanings 2-12, three zones of stability are observed, which alternate with three zones of coagulation. Within the limits of these zones ξ-potential change its sign three times. It has been stated that the recharging of MMТ surface cannot be caused by simple adsorption of Cr3+ ions, but by the products of their hydrolysis.