The purpose of the paper was the production of calciumcarbonate or calciumhydroxid slurrys. The slurrys should be very fine, with a hight content of solids, to yield a very hight degree of impregnation, when impregnating a refractory. Suitable raw materials, dispersing agents and the optimal contents of the latter, for the production of the slurrys, where chosen by particle charge detection and grinding experiments. The resulting slurrys were used to impregnate a refractory (basis magnesia and chromite). The best result was an impregnation degree of 87,4%.