A mold, for producing molded blocks with at least one lateral face which has a texture, comprises a mold lower part and at least one flexible belt, wherein the flexible belt surrounds at least one mold wall of the mold lower part that delimits a mold cavity of the mold lower part in order to act on the material for producing the molded block that is received in the mold cavity, to impress a texture on at least one of the lateral faces of the molded block, wherein the flexible belt is moveable relative to the mold lower part and is mounted in such a way that the flexible belt moves around the mold wall when the molded block is ejected from the mold cavity. The mold comprises an active auxiliary device by means of which a rolling resistance of the flexible belt can be varied.