Paul Reich, whose early works resemble the early Informel work of Herbert Hajek, is the first Informel sculptor to work almost excessively with the medium of acrylic glass and to combine it with the basically incompatible materials of metal and stone. In his light sculpture "S.u.W./63", from 1963, a core of slaggy stone without clearly recognizable boundaries is enriched by vertically inserted aluminum parts, which in turn enclose and in part even "violate" the corrugated, spalted acrylic glass panes, which are arranged several times in a row. Although the sculpture obeys architecturally correct principles, in that weighting is assigned to stone, supporting to metal, and floating to glass, the use of heterogeneous materials is completely forgotten. By including acrylic glass and its visual spatiality, Reich thematizes light permeability and achieves an interlocking with space. Kurt Leonhard aptly summed up Reich's approach, which remains unique to this day, with the following sentence: "Air now seemed to have become representable for sculpture as well."