![]() Umber pigments contain a larger proportion of manganese (5-20%), which makes them a dark brown.Sienna contains both limonite and a small amount of manganese oxide (less than 5%), which makes it darker than ochre.Brown ochre, also FeO(OH), ( goethite), is a partly hydrated iron oxide.Purple ochre is identical to red ochre chemically but of a different hue caused by different light diffraction properties associated with a greater average particle size.The major ingredient of all the ochres is iron(III) oxide-hydroxide, known as limonite, which gives them a yellow colour.ĢO, is a hydrated iron hydroxide (limonite) also called gold ochre.ģ, takes its reddish colour from the mineral hematite, which is an anhydrous iron oxide. Ochre is a family of earth pigments, which includes yellow ochre, red ochre, purple ochre, sienna, and umber. The word ochre also describes clays coloured with iron oxide derived during the extraction of tin and copper. A variant of ochre containing a large amount of hematite, or dehydrated iron oxide, has a reddish tint known as "red ochre" (or, in some dialects, ruddle). It is also the name of the colours produced by this pigment, especially a light brownish-yellow. It ranges in colour from yellow to deep orange or brown. ![]() Ochre ( / ˈ oʊ k ər/ OH-kər from Ancient Greek ὤχρα ( ṓkhra), from ὠχρός ( ōkhrós) 'pale'), or ocher in American English, is a natural clay earth pigment, a mixture of ferric oxide and varying amounts of clay and sand. For the indigenous people of North America, see Red Ocher people. ![]()
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