Difference between revisions of "Raw umber"

From CAMEO
Jump to navigation Jump to search
(username removed)
 
 
(3 intermediate revisions by 2 users not shown)
Line 1: Line 1:
 
[[File:Raw.umber_det.jpg|thumb|Raw umber]]
 
[[File:Raw.umber_det.jpg|thumb|Raw umber]]
 
== Description ==
 
== Description ==
 
+
[[File:564 raw umber.jpg|thumb|Raw umber]]
A pale yellowish brown natural earth pigment that contains [http://cameo.mfa.org/materials/fullrecord.asp?name=manganese%20dioxide manganese dioxide] and [http://cameo.mfa.org/materials/fullrecord.asp?name=ferric%20hydroxide iron hydroxide]. See [http://cameo.mfa.org/materials/fullrecord.asp?name=umber umber].
+
A pale yellowish brown natural earth pigment that contains [[manganese%20dioxide|manganese dioxide]] and [[ferric%20hydroxide|iron hydroxide]]. See [[umber|umber]].
  
 
== Synonyms and Related Terms ==
 
== Synonyms and Related Terms ==
Line 8: Line 8:
 
Pigment Brown 7; CI 77492; umbra; terre d'ombre naturelle (Fr.); Umbra natur (Deut.);  ombra omi (Gr.); terra d'ombra naturale (It.); ruwe omber (Ned.); grisaille; Sicilian brown
 
Pigment Brown 7; CI 77492; umbra; terre d'ombre naturelle (Fr.); Umbra natur (Deut.);  ombra omi (Gr.); terra d'ombra naturale (It.); ruwe omber (Ned.); grisaille; Sicilian brown
  
[[File:564 raw umber.jpg|thumb|Raw umber]]
+
== Risks ==
== Other Properties ==
+
 
 +
Toxic.
 +
== Physical and Chemical Properties ==
  
 
Slightly soluble in acids giving a yellow solution. Turns reddish brown when heated.
 
Slightly soluble in acids giving a yellow solution. Turns reddish brown when heated.
Line 16: Line 18:
 
|-
 
|-
 
! scope="row"| Density
 
! scope="row"| Density
| 3.2
+
| 3.2 g/ml
 
|-
 
|-
 
! scope="row"| Refractive Index
 
! scope="row"| Refractive Index
 
| 1.87-2.17
 
| 1.87-2.17
 
|}
 
|}
 
== Hazards and Safety ==
 
 
Toxic.
 
 
 
== Additional Images ==
 
== Additional Images ==
  
 
<gallery>
 
<gallery>
File:21_Raw umber_500X.jpg|Raw umber
+
File:21_Raw umber_500X.jpg|Raw umber at 500s<br> transmitted light
File:21_Raw umber_500X_pol.jpg|Raw umber
+
File:21_Raw umber_500X_pol.jpg|Raw umber at 500x<br>Polarized light
 
</gallery>
 
</gallery>
  
 
+
== Resources and Citations ==
== Authority ==
 
  
 
* R. J. Gettens, G.L. Stout, ''Painting Materials, A Short Encyclopaedia'', Dover Publications, New York, 1966  Comment: density = 3.20 and ref. index = 1.87-2.17
 
* R. J. Gettens, G.L. Stout, ''Painting Materials, A Short Encyclopaedia'', Dover Publications, New York, 1966  Comment: density = 3.20 and ref. index = 1.87-2.17
Line 44: Line 40:
 
* ''Dictionary of Building Preservation'', Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996
 
* ''Dictionary of Building Preservation'', Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996
  
* Website address 1  Comment: Pigments Through the Ages - http://webexhibits.org/pigments/indiv/overview/umbra.html
+
* Pigments Through the Ages - http://webexhibits.org/pigments/indiv/overview/umbra.html
  
* Website address 2  Comment: http://www.coloria.net/varita.htm
+
* Website: http://www.coloria.net/varita.htm
  
 
* Art and Architecture Thesaurus Online, http://www.getty.edu/research/tools/vocabulary/aat/, J. Paul Getty Trust, Los Angeles, 2000
 
* Art and Architecture Thesaurus Online, http://www.getty.edu/research/tools/vocabulary/aat/, J. Paul Getty Trust, Los Angeles, 2000

Latest revision as of 16:56, 4 August 2022

Raw umber

Description

Raw umber

A pale yellowish brown natural earth pigment that contains Manganese dioxide and iron hydroxide. See Umber.

Synonyms and Related Terms

Pigment Brown 7; CI 77492; umbra; terre d'ombre naturelle (Fr.); Umbra natur (Deut.); ombra omi (Gr.); terra d'ombra naturale (It.); ruwe omber (Ned.); grisaille; Sicilian brown

Risks

Toxic.

Physical and Chemical Properties

Slightly soluble in acids giving a yellow solution. Turns reddish brown when heated.

Density 3.2 g/ml
Refractive Index 1.87-2.17

Additional Images

Resources and Citations

  • R. J. Gettens, G.L. Stout, Painting Materials, A Short Encyclopaedia, Dover Publications, New York, 1966 Comment: density = 3.20 and ref. index = 1.87-2.17
  • Michael McCann, Artist Beware, Watson-Guptill Publications, New York City, 1979
  • R.D. Harley, Artists' Pigments c. 1600-1835, Butterworth Scientific, London, 1982
  • Dictionary of Building Preservation, Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996