A unit for mixing materials generally in powder form, comprising a support frame for a rotary plate above which there are positioned at least two members for dispensing powders having different characteristics, their position being adjustable relative to said plate, with said plate there being associated, rigid with said frame, a fixed hollow cylindrical body for containing said powders and comprising in proximity to said plate at least one material discharge aperture with which there is associated at least one deviator element arranged to convey said powders towards said discharge aperture. |