Description
Any of several naturally occurring earth pigments containing clay and iron oxide. Ochers range in color from pale yellow to orange to deep red. The yellow and brown colors are produced from hydrated iron oxide and the reds from anhydrous iron oxide. Yellow ocher can also be calcined at 550-600 C to form red ocher. Depending on their originating location, ochers can contain small amounts of sand, chalk, gypsum, barite, and silicates that produce variations in color and tinting strength. All ochers, however, are very durable, inert, and lightfast. They have been used since ancient times as permanent pigments in all types of paint media. They are also used as colorants in ceramic slips and glazes. Ocher is often added as a reducing agent in luster glazes.
Synonyms and Related Terms
haematite; limonite; ochre (Br.); ocre (Fr., Port.); Examples include: golden ochre; English ocher; Roman ochre; sienna; oro de ocre; Oxford ochre; terra di pozzuoli; terra rosa; red chalk; bole; red iron ore; iron oxide red; bolus; sinopia; rubica; ruddle; Venetian red; Indian red; light red
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Last updated on: 3/14/2010 6:32:06 PM
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