Ochre quarry, Rustrel, Provence, France. Ochre is a pigment formed in clay by iron oxide that varies in colour from yellow to purple. It was extracted in Provence from several sites that are now closed to production. At the Rustrel Colorado site the clay, a kaolinite, is mainly the yellow and brown ochres that are created by limonite and geothite, different forms of iron oxide that mix and blend to form the tints in between. Until modern times, large quantities were mined for paint pigments. It was also used to colour foodstuffs, cosmetics, wallpaper, linoleum, rubber products and as a medicine. Being non-toxic it was very safe to use. Early man used ochre for their cave paintings and in Africa it has been used for 200,000 years.