The invention relates to a method for the production of molds for casting purposes, and parts of the same made of a granular, fireproof material and a binding agent, particularly shell molds, sand cores, and parts thereof. For this purpose two devices are utilized having parts, onto which a composition is applied before the use thereof, said composition comprising at least one silicon-organic component. The invention further relates to the use of such a composition for the production of molds for casting purposes, and to a corresponding device. The latter is characterized in that it comprises at least one part that is equipped with a silicon-organic layer or coating.