The invention relates to the method for production of preparation (sorbent) for removing and immobilisation of heavy metals cations and phosphates in contaminated solid or liquid phase as a composite, grainy material, which consists of the bearing component of the type of natural slates and/ or waste after the coal modification, of the active immobilisation component of the type of thermally modified dolomites with high content of MgO. CaCO3 and sealing binder, preferably cement, in mutual ratio (1.3 to 4.3) : (1.0 to 1.3) : 1.0 to 1.5). Of the prepared mixture the substance of the sealing consistence is prepared by adding the diluting water with coefficient 1.25 to 2.0, and the substance is stiffened during 3 to 7 days, then is ground and this material is separated into the various fractions with pre-defined size of grains, preferably (1.0 to 3), (0.1 to 1.0) and (less than 0.3) mm. The use of the sorbent for purification of contaminated solid or aqueous phase is determined by a selection of applied fraction
