Burnt umber
Revision as of 06:42, 24 July 2013 by (username removed)
Description
A chocolate brown iron ore pigment made by roasting raw umber. Burnt umber contains iron oxide and manganese dioxide. The heat treatment converts the yellowish iron hydroxides to brownish iron oxides which produces a dark brown pigment with a reddish tone. Burnt umber is a permanent pigment that has been used in oil and watercolor paints.
Synonyms and Related Terms
Pigment Brown 7; CI 77492; terre d'ombre brûlée (Fr.); Gebrannte Umbra (Deut.); sombra tostada (Esp.); ombra psimenii (Gr.); terra d'ombra bruciata (It.); bruno di Roma (It.); bruine omber (Ned.); Caledonia brown; Cappagh brown; mineral brown; Turkey umber; jacaranda brown; chestnut brown;
| Density | 3.64 |
|---|---|
| Refractive Index | 2.2 - 2.3 |
Hazards and Safety
Toxic by ingestion. May cause manganese poisoning.
Authority
- R. J. Gettens, G.L. Stout, Painting Materials, A Short Encyclopaedia, Dover Publications, New York, 1966 Comment: density 3.64 and ref. index 2.2-2.3
- G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 558
- Michael McCann, Artist Beware, Watson-Guptill Publications, New York City, 1979
- R.D. Harley, Artists' Pigments c. 1600-1835, Butterworth Scientific, London, 1982
- Matt Roberts, Don Etherington, Bookbinding and the Conservation of Books: a Dictionary of Descriptive Terminology, U.S. Government Printing Office, Washington DC, 1982
- Dictionary of Building Preservation, Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996
- Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
- The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
- Art and Architecture Thesaurus Online, http://www.getty.edu/research/tools/vocabulary/aat/, J. Paul Getty Trust, Los Angeles, 2000