The invention relates to a process for making a product of artificial rock and a product thus made for use, in particular, in aquariums, tanks, swimming pools and the like; the process comprises the following operating steps: carrying out a first deposition of a mixture of powdered aggregates, resin, additives, within a cast or mould; catalyzing the mixture of said first deposition; covering the surface thus obtained with isophtalic or bisphenolic polyester resin; carrying out a second deposition of powdered aggregates, resin, additives; covering the surface derived from the second deposition with a layer of structural component and with resin; polymerizing the intermediate product thus obtained covering the surface thus obtained with a layer of gel; polymerizing the product thus obtained; removing the product from the mould; subjecting the product to a heating treatment.