Corroso

Kind of glass whose surface is irregular to the touch due to the use of chemical agents. Technically, an "acid process" is caused by the corrosion of the glass surface that provokes the disintegration of the glass lattice: the result is the creation of a rough layer on the surface. This non-uniform layer causes an effect of partial diffusion and reflexion of the light. For its execution, solutions of hydrofluoric acid and ammonium fluoride in water are commonly used. By varying temperature, time in the bath and composition of the same, it is possible to obtain very varied effects. The parts of the glass surface to be kept bright are plated with wax or some other organic protective agent. This technique was introduced by the French at the beginning of the 20th century and found its first applications in Murano in the mid-30s applied to a series of "corrosi" wares designed by Carlo Scarpa for Venini & Co. and to the vases and figured designed by Flavio Poli for the Seguso Vetri d'Arte firm. Fallen progressively out of use, this technique is to this day very strictly regulated from the new anti-pollution regulation, because of the high toxic level of the materials used durign the production process.