Larry Bell, Billy Al Bengston, and Ken Price outside Hotel Caesars in Tijuana, Mexico, 1968. Image courtesy of Larry Bell

Exterior view of Larry Bell's studio on Market Street in Venice, California, ca. 1970. Image courtesy of and © Larry Bell

Installation view of Craig Kauffman's solo exhibition at the Pasadena Art Museum, including works from Kauffman's Loops series, 1970. Photo by Frank J. Thomas. Courtesy of the Frank J. Thomas Archives

View of Market Street in Venice, California, in 1970, showing the studio buildings of Larry Bell (right) and Robert Irwin (left). Photo by Larry Bell. Courtesy of and © Larry Bell

Robert Irwin and James Turrell inside the anechoic chamber at UCLA, 1969. Image courtesy of Malcolm Lubliner and Craig Krull Gallery, Santa Monica. © Malcolm Lubliner

Larry Bell in his studio in Venice, California, ca. late 1960s. Image courtesy of and © Larry Bell

Announcement for Doug Wheeler exhibition at Ace Gallery in Los Angeles , 1970. Printed plastic. © Doug Wheeler. The Getty Research Institute, Gift of George Herms, 2009.M.20.6

Poster for Craig Kauffman exhibition at Ferus Gallery in Los Angeles, 1962. © The Estate of Craig Kauffman. The Getty Research Institute, Gift of Michael Asher, 2009.M.30.16. Courtesy Frank Lloyd Gallery, Santa Monica, California

Red Concave Circle, 1970, De Wain Valentine. Cast polyester resin. 96 x 96 x 12 in. Bank of America Collection. © De Wain Valentine. Photo: Harry Drinkwater

Untitled, 1970, Frederick Eversley. Three-color, three-layer cast polyester. 20 x 20 x 6 in. Collection of the artist. © Frederick Eversley

Untitled, 1969, Larry Bell. Mineral-coated glass. 40 x 40 x 40 in. Courtesy The Pace Gallery. © Larry Bell. Photo by Ellen Labenski

Untitled, 1969, Helen Pashgian. Cast sphere, color polyester resin. 7 in. diam. Norton Simon Museum, Gift of the artist. © Helen Pashgian

Untitled, 1969, Craig Kauffman. Acrylic lacquer on plastic. 73 x 50 x 9 in. Courtesy the Estate of Craig Kauffman and the Frank Lloyd Gallery. © The Estate of Craig Kauffman

Untitled (Leaner), 1970, Peter Alexander. Polyester resin. 104 ½ x 5 ½ x 3 in. Collection of the artist. © Peter Alexander

Untitled (White Light Grid Series-V), 1969, Mary Corse. Glass microspheres in acrylic on canvas. 108 x 108 in. Andrea Nasher Collection. Permission courtesy Ace Gallery and the artist