A material composition for play or modelling purposes includes a particulate material and a binder which is disposed as thin layers on the particles. T-he binder includes a hydroxy-terminated polymer cross-linked by a boron compound, in particular a silicone oil. The concentration of particles is 90-98 vol % of the finished composition. A method for producing the material composition includes placing the particles in a mixer, adding the hydroxyl-terminated polymer, in particular silicone oil, and distributing it as thin layers on the surfaces of the particles and, thereafter, adding a boron-containing cross-linking agent in solution and mixing so that a cross-linking of the polymer takes place and the viscosity increases.