A process for effecting the fixation of substances to one another, comprises the steps of (a) intimately mixing finely divided non-fibrous particles, exhibiting a negative electrostatic charge, with a diluted colloidal dispersion in water of a water insoluble sticky (i.e., non-oxidising) resinous body in a liquid immiscible with water, whereby the emulsion is broken and sticky colloidal particles of the solution are deposited on the non-fibrous particles, (b) adding a water soluble metallic sulphate to form a magma of coated particles powerfully attracted and adherent to fibres or particles exhibiting a negative electrostatic surface charge, and (c) adding an aqueous suspension of the fibres or particles to be fixed to the non-fibrous particles. Specified non-fibrous particles are those of china clay, kieselguhr and chalk, and a preferred resin solution is a kerosene solution of the diethylene glycol ester of polymerised rosin plasticized with a phthalic anhydride-glycerol resin. Other specified resinous bodies are alkyd resins, ester gums, pentaerythritol abietate, diethylene glycol abietate, especially when polymerised, cooked or extended with soya bean oil, linseed oil, or castor oil. The water for diluting the colloidal dispersion may contain particles of dye precipitated by metallic ions from an aqueous solution of an acid or basic dye immediately after the addition of such ions and immediately before the admixture of the non-fibrous particles, whereby the particles of dye are deposited simultaneously with the colloidal particles of resin solution to form a veneer of dye on the non-fibrous particles in the magma. Alternatively the water may contain an acid or basic dye capable of being precipitated by the colloidal particles of resin solution. The process is also applicable to the production of compound pigments, useful as pigments in paints, enamels or distempers, in which the relatively inexpensive non-fibrous particles are veneered with a more expensive pigment such as titanium dioxide. Specification 554,085 is referred to.ALSO:A process for effecting the fixation of substances to one another comprises the steps of (a) intimately mixing finely-divided non-fibrous particles, exhibiting a negative electrostatic charge, with a diluted colloidal dispersion in water of a water-insoluble sticky (i.e. non-oxidising) resinous body in a liquid immiscible with water, whereby the emulsion is broken and sticky colloidal particles of the solution are deposited on the non-fibrous particles, (b) adding a water-soluble metallic sulphate to form a magma of coated particles powerfully attracted and adherent to fibres or particles exhibiting a negative electrostatic surface charge, and (c) adding an aqueous suspension of the fibres or particles to be fixed to the non - fibrous particles. Specified non - fibrous particles are those of china clay, kieselguhr and chalk, and a preferred resin solution is a kerosene solution of the diethylene glycol ester of polymerized resin plasticised with a phthalic anhydride - glycerol resin. Other specified resinous bodies are alkyd resins, ester gums, pentaerythritol abietate, diethylene glycol abietate, especially when polymerized, cooked or extended with soya bean oil, linseed oil or castor oil. The water for diluting the colloidal dispersion may contain particles of dye precipitated by metallic ions from an aqueous solution of an acid or basic dye immediately after the addition of such ions and immediately before the admixture of the non - fibrous particles, whereby the particles of dye are deposited simultaneously with the colloidal particles of resin solution to form a veneer of dye on the non-fibrous particles in the magma. Alternatively, the water may contain an acid or basic dye capable of being precipitated by the colloidal particles of resin solution. Specification 554,085, [Group III], is referred to.ALSO:A process for effecting the fixation of substances to one another, comprises the steps of (a) intimately mixing finely divided non-fibrous particles, exhibiting a negative electrostatic charge, with a diluted colloidal dispersion in water of a water insoluble sticky (i.e., non-oxidising) resinous body in a liquid immiscible with water, whereby the emulsion is broken and sticky colloidal particles of the solution are deposited on the non-fibrous particles, (b) adding a water soluble metallic sulphate to form a magma of coated particles powerfully attracted and adherent to fibres or particles exhibiting a negative electrostatic surface charge, and (c) adding an aqueous suspension of the fibres or particles to be fixed to the non-fibrous particles. Specified non-fibrous particles are those of china clay, kieselguhr and chalk, and a preferred resin solution is a kerosene solution of the diethylene glycol ester of polymerized rosin plasticized with a phthalic anhudride-glycerol resin. Other specified resinous bodies are alkyd resins, ester gums, pentaerythritol abietate, diethylene glycol abietate, especially when polymerized, cooked or extended with soya bean oil, linseed oil or castor oil. The water for diluting the colloidal dispersion may contain particles of dye precipitated by metallic ions from an aqueous solution of an acid or basic dye immediately after the addition of such ions and immediately before the admixture of the non-fibrous particles, whereby the particles of dye are deposited simultaneously with the colloidal particles of resin solution to form a veneer of dye on the non-fibrous particles in the magma. Alternatively the water may contain an acid or basic dye capable of being precipitated by the colloidal particles of resin solution. Specification 554,085, [Group III], is referred to.