Abstract: Zinc silicates were synthesized under conditions analogous to surficial weathering environments. The main product, regardless of conditions of precipitation or ageing, was shown by X-ray, i.r., electron microscopic and chemical evidence to be a 2:1 layered zinc silicate equivalent of stevensite. In the presence of aluminium, a 1:1 layered zinc silicate was formed as well, in confirmation of published work. The stability of the zinc silicate, in relation to carbonate, was favoured by the presence of aluminium in the lattice and silicic acid in the equilibrium solution. Zinc layer silicates were formed under conditions that generated orthorhombic zinc hydroxides and/or basic salts in the absence of silicon; the involvement of the brucitic zinc hydroxide (α-form), as proposed by earlier workers, could not be supported. Crystalline zinc layer silicates were formed by the slow evolution of the initial gels. Such layer silicates, but not willemite or hemimorphite, could have an important role in the control of chemical reactions of zinc in soils.