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ocher

A name given to various native earthy materials used as pigments. They consist essentially of hydrated ferric oxide admixed with clay and sand in varying amounts and in impalpable subdivision. When carrying much manganese ochers grade into umbers. 2153 They are either yellow, brown, or red. The best reds are sometimes obtained by calcining the yellow varieties. They are called burnt ochers. Others are obtained by calcining copperas or as a residue from roasting pyrite. In general, the native yellows and browns are varieties of limonite and the native reds are varieties of hematite. One variety of red ocher is known as scarlet ocher. Their value as pigments depends not only on the depth of color but also on the amount of oil required as a vehicle.

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  • ed.young
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