A material composition for play or modelling purposes comprises a particulate material (2) and a binder (3) which is disposed as thin layers on the particles. The binder includes a hydroxy-terminated polymer cross-linked by a boron compound, in particular a silicon oil. According to the present invention, the concentration of particles (2) is 90-98 vol% of the finished composition. A method for producing the material composition comprises the steps that the particles (2) are placed in a mixer, that the hydroxyl-terminated polymer, in particular silicon oil, is added and distributed as thin layers on the surfaces of the particles and that thereafter a boron-containing cross-linking agent is added in solution and mixed so that a cross-linking of the polymer takes place and the viscosity increases.