Alchemy, the transmutation of material and transformation of form, is a constant theme of Polke’s work. He uses colours that are no longer produced, such as toxic Schweinfurt green or orpiment made from arsenic; he uses natural pigments like crimson (Purpur, 1986) or lapis lazuli (Lapis Lazuli II, 1994) and mixes metallic powders like resin, enamel, and lampblack; he pushes his experiments with colour to a highly sophisticated level (Farbprobe, 1982-1993). IPolke constantly challenges the materials and their chemical-physical properties. Introducing unforseeable variables, he generates imponderable chemical reactions, explosive meetings and hybrid unions. The pictorial cycle of 1995, exhibited on the first floor at Palazzo Grassi is dedicated, not by coincidence, to Hermes Trismegistus (Hermes Trimegistos I-IV, 1995), a legendary figure of the pre-classical age, patron of alchemists and father of hermetic philosophy.