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Red ochre

Red ochre and yellow ochre (pronounced OAK-ur, from the Greek ochros, yellow) are pigments made from naturally tinted clay. It has been used worldwide since prehistoric times. Chemically, it is anhydrous iron (III) oxide.

Ochres are non-toxic, and can be used to make an oil paints that dry quickly and cover surfaces thoroughly. Many sources consider the best ochre to come from Roussillon, France.

To manufacture ground ochre, ochre clay is first mined from the ground. It is then washed in order to separate sand from ochre, which can be done by hand. The remaining ochre is then dried in the sun and sometimes burned to enhance the natural color.

History

Ochre was one of the first pigments to be used by human beings. Pieces of hematite, worn down as though they had been used as crayons, have been found at 300,000 year old Homo heidelbergensis sites in France and Czechoslovakia. Neandertal burial sites sometimes include ochre as a grave good. The oldest evidence of mining activity, at the "Lion Cave" in Swaziland, is a 43,000 year old ochre mine. In Germanic rune lore, red ochre was often used in place of blood to redden, or tint, the runes and thereby instilling the spirit of life into the rune, enabling it to be used for magical purposes.

Ochre was a popular coloring in France during the time of the French Empire, and many French citizens in living in foreign colonies would import a great deal of ochre clay from France to make their new lands feel like home. As a result, after the period of French colonization ended, ochre became associated with repression and fell out of favor. With the advent of synthetic dyes , ochre mining nearly stopped altogether. Recently, however, natural ochre paint has seen something of a comeback as an upscale housepaint option.

See Also

Further reading

  • Red Ochre and Yellow ochre, from Pigments through the ages.
  • A recipe for red ochre paint.
  • Fuller, Carl; Natural Colored Iron Oxide Pigments, pp. 281-6. In: Pigment Handbook, 2nd Edition. Lewis, P. (ed.). New York: John Wiley & Sons, 1988.
  • Thomas, Anne Wall. Colors From the Earth, New York: Van Nostrand Reinhold, 1980.
10-26-2009 08:16:03
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