In successive publications the authors have demonstrated that the galvanic cell model is valid in the corrosion of marbles, just as in metals. Further research indicates that marbles could be protected by sulphation by using anticorrosive coal tar epoxy. Since a black coating would be unsuitable, other materials with similar properties were tested in synthetic-resin vehicles. The invention of a material possessing such properties and complying with the Venice Charter could help in the protection of marbles. Figures, references.