The artist began working with enamel on aluminum in 1984, when he commissioned Lehni AG in Switzerland to construct works by bending and riveting thin sheets of the material, a process Judd previously used to create furniture. These pieces were initially created for a temporary outdoor exhibition in Merian Park outside Basel. Judd would continue to produce pieces using these techniques through the early 1990s. Judd’s work with enamel on aluminum greatly expanded his palette of colors, which had previously been restricted to the colors of anodized metal and Plexiglas, and led to the use of more than two colors in an individual artwork. Combining a wide range of colors, he used the material to create five large-scale floor pieces and many horizontal wall works in unique variations of color and size. Judd’s only known work in granite, an untitled Sierra White granite floor piece from 1978, measures 72 x 144 x 12". The structure is composed of two vertical slabs that rest on the floor, to which the bottom component is conjoined, and the ceiling of the structure extends to the outer edges of the vertical walls.