Decommissioned ochre quarry, Roussillon, 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 Roussillon site the clay, a kaolinite, is in the yellow/orange/red and purple range of colours. Purple is created by hematite, iron III oxide, but the particle size is larger than red ochre. 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 humans used ochre for their cave paintings and in Africa it has been used for 200,000 years.