Cerium oxide, dispersion containing silicon dioxide and amino acids

A dispersion comprising one or more amino acids and / or salts thereof in the case of particles and colloidal silicon dioxide as well as each of the cerium oxide, the zeta potential of the silicon dioxide particles is negative and cerium oxide things zeta potential of the particles is equal to a positive or zero, and a negative overall zeta potential of the dispersion, or less average grain size for cerium oxide particles is 200 nm, silicon dioxide particles be less than 100nm for content, a 0.1 to 5 wt% cerium oxide particles, based on the total amount of the dispersion in each case, and - amino acids are silicon dioxide particles 0.01 to 10 mass% or its salt is 0.01 to 5 mass% and - pH of the dispersion is 7.5 to 10.5, dispersion.