Stabilized, spherical, amorphous calcium carbonate particles having a mean particle diameter in the range from 0.05 μm to 2.0 μm and a water content of at most 5.0 wt % measured as residual moisture at 200° C., wherein the calcium carbonate particles comprise at least one substance which has a molar mass greater than 100 g/mol and satisfies the formula R—Xn, wherein the radical R represents a radical comprising at least one carbon atom, the radical X represents a group which comprises at least one oxygen atom and at least one carbon atom, sulphur atom, phosphorus atom and/or nitrogen atom and n preferably constitutes a whole number in the range from 1 to 20, the proportion of crystalline calcium carbonate is less than 30 wt %, and the specific surface area of the calcium carbonate particles is at most 20 m2/g.