Between 1939 and 1952 Giulio Radi, who was at that time director of A.VE.M, developed this technique. He experimented with different degrees of the coefficients of expansion in combination with gold and silver and achieved extraordinary effects. Different layers of thick glass could vary them again. The master glassblower Luciano Ferro executed most objects. The 33rd Biennale held a retrospective. In the 60s, Aldo Nason took up this technique again for his series 'Yokohama'.