These artists’ radical reduction of the palette—which extended beyond paintings to encompass reliefs and sculptures—highlighted art’s potential to move beyond its longstanding role of representing the visible world and of reflecting the subjectivity of the artist.
Yves Klein’s Monochromes proved especially influential for artists in the ZERO network. He applied a dense expanse of pigment across the surface and around the edges of his unframed pictures. This approach resulted in works that emphasize pure color and appear almost to be objects floating off the wall. At the same time, Klein’s monochromes allude to abstract ideas and metaphysical concepts, such as the immaterial, space, and the void. The older but no-less-influential Italian artist Lucio Fontana opened up new horizons with his Concetti spaziali (1947–68), a series that includes single-color paintings with slashes that direct attention to the space beyond the picture plane. Otto Piene used stencils to lay paint on canvas in grid-like patterns intended to call attention to the play of light. In a related approach, Brazilian artist Almir Mavignier created works with patterns of colored paint droplets with pointed tips that emphasize light and shadow and have a discernible physical impact on the retina. Heinz Mack applied serial lines to his monochrome paintings and reliefs to generate a sensation of dynamism that makes the surface seem to vibrate. Günther Uecker enlivened the surface of his monochromes with utilitarian materials like corks and nails, while Enrico Castellani used nails to create pictures that initially look like flat, single-color paintings, yet upon closer examination reveal themselves to be dimensional reliefs. Other members of the ZERO network also turned to everyday materials ranging from cotton threads to roof tiles. In his Achromes (1957–63), Piero Manzoni tested the limits of the medium by employing unusual, colorless materials like bread and Styrofoam, and herman de vries added sand to white paint in a series of sculptures that reflect his desire to create “homogeneous structures.”