Dalles de verre (small slabs of coloured glass, usually about 2 cm thick) started to be popular in the 1930s. Dalles de verre panes are made by cutting the slabs with a water cooled diamond tipped saw or a chisel with a carbide tip.
The individual pieces are placed on a flat surface covered with a plastic sheet following the design. They are kept in place with cement or epoxy resin.
The main characteristic of this technique is the refraction of light that can be achieved: the slab can be cut both vertically and obliquely creating rough dishomogeneous surfaces that thus enhance intense and variable plays of light.
