Description
An old name for a soft, blue-black variety of a clay formed from aluminum containing slate. Black chalk obtains its color from impurities of carbon, black iron oxide, or manganese oxide. It was sometimes used as a crayon or writing tool, especially since the Rennaisance. Black chalk was mined in Thuringia, parts of France and Andalucia. Sometimes graphite was also referred to as black chalk.
Synonyms and Related Terms
craie noire (Fr.); lapiz negro (Esp.); grafite (It.); piombaggine (It.); mineral black; black earth; Italian chalk
Hazards and Safety
No significant hazards.
Additional Information
J.Winter, "The Characterization of Pigments Based on Carbon" Studies in Conservation 28:49-66, 1983.
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Last updated on: 7/22/2009 2:10:55 PM
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