A naturally occurring earth, or mineral pigment, which comes in a vast array of colours and tones, from the palest of yellows to brown-reds and greens depending on its ferric oxide, silica and alumina levels. It is a pre-historic pigment used in cave paintings and as an early form of paint. It remains an important constituent of modern artist and interior paints, distempers, coloured paper and metal primers. Red ochre, yellow ochre, green earth, sienna and umber are just some of the many types of ochre.
