Artist's Palette, on the face of the Black Mountains, exhibits a variety of colors created by the oxidation of different metals (red, pink and yellow is from iron salts, green is from decomposing tuff-derived mica, and manganese produces the purple) as well as chemical weathering and hydrothermal alteration. Death Valley National Monument Est. February 11, 1933. Est. as Death Valley National Park in 1994; 5,270 square miles (13,649 km2). Inyo County, CA.