Pots of powdered ochre pigment. The traditional pigment for the earthy colours has been ochre for millennia. Once processed, a matter of extracting the pure pigment from the clays and sands in which it is formed, it can be used with water or oil to make an artists material or to colour and dye. It is very stable, non-toxic and easy to mix. While the colours occur naturally they can be adjusted with heat and blending to create a wider palette. 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. The Okhra Ecomusee de locre in Roussillon produces this range of pigments and is on the site of one of the local ochre manufacturers whose buildings and machinery can be visited.