Yellow ocher, sienna, and umber are oxides of iron. Litharge is a yellow oxide of lead. Red lead is also an oxide of this metal. Lead chromate, or chrome yellow, is an important yellow pigment. Cadmium yellow is a sulfide of cadmium.
Green pigment is produced by mixing Prussian blue and chrome yellow.
Pigments occur in plant and animal bodies. Among others are carotene, the yellow of carrots and certain other vegetables, and anthocyanin, which imparts blue, red, and purple to flowers. Blood receives its color from the hemoglobin in the red corpuscles.