Stains, 1969
Portfolio of Seventy-five mixed media stains and one stain on the inside cover of the box
Print dimensions vary; each sheet approx 30 x 27 cm
Tate

As a colour chart, Ruscha's Stains portfolio is almost absurdly humble. Although the materials he used to create it are numerous and diverse, their visual effect is far from dazzling. Many of the stains fail even as stains, being invisible or nearly so. Ruscha was careful to keep personal expression to a minimum, going so far as to hire other people to drip each of the liquids on its page using an eyedropper: 'I didn't want it to look like art. I wanted it to look like a stain.'

News, Mews, Pews, Brews, Stews, Dues, 1970
Portfolio of six organic screenprints
Print dimensions vary; each sheet approx 59 x 81 cm
Tate

These six screenprints began as shopping expeditions for products as diverse as baked beans, mango chutney, and tulips. Ruscha used a mortar and pestle to crush these ingredients and formulate bizarre recipes for organic inks. He accepted the unpredictability of the colour they would yield for his prints: 'Hey, I had no choice in the selection of color for the food prints – how do you alter the colour of caviar or axle grease?' Ruscha worked on the project with a printer in London and chose the six titles for their association with British things.