X-ray diffraction analysis of pictograph pigments from Toquima Cave, central Nevada

X-ray diffraction analysis of red, yellow, white, and black pigments from pictographs in Toquima Cave in central Nevada reveals that gypsum was used as a binder in all colors; ocher (hematite and goethite) and carbon (charcoal) formed the coloring agents. Gypsum and ocher are not found in or near the cave, so the paint mixtures were made from ingredients found elsewhere and then transported to the site of the paintings.