nyuuzyou/wikis huggingface dataset:
Chloropicrin

== Description ==
A colorless, oily liquid that causes eyes to water. Chloropicrin is a highly toxic irritant used in tear gas, dyes, disinfectants, and insecticides. It has also been used as a wood preservative. Trace amounts of chloropicrin are added to odorless fumigants (methyl bromide, sulfuryl fluoride) to act as a warning agent. However, unless the air is dry, chloropicrin may corrode metals.
== Synonyms and Related Terms ==
chlorpicrin; nitrochloroform; nitrotrichloromethane; trichloronitromethane; acquinite; klop; Larvacide; Picfume; TimberFume®
== Risks ==
* Highly toxic by inhalation, ingestion, and skin absorption. 
* Lachrymator, strongly irritating to eyes and tissues. Corrosive to metals. 
* Fisher Scientific: MSDS
== Physical and Chemical Properties ==
Soluble in ethanol, benzene, ether, carbon disulfide. Insoluble in water and acids.
Composition 	CCl3NO2
CAS 	76-06-2
Melting Point 	-69.2 C
Density 	1.692 g/ml
Molecular Weight	mol. wt. = 164.37
Boiling Point 	112 C
== Resources and Citations ==
* Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
* The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 2208
* The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
* Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
* G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 622
* Lynda A. Zycherman, J.Richard Schrock, A Guide to Museum Pest Control, FAIC and Association of Systematics Collections, Washington DC, 1988
* Matt Roberts, Don Etherington, Bookbinding and the Conservation of Books: a Dictionary of Descriptive Terminology, U.S. Government Printing Office, Washington DC, 1982
Category:Materials database
Chloroplatinic acid

== Description ==
Reddish brown light sensitive crystals. Chloroplatinic acid is used to make platinum photographic prints, indelible ink, and mirrors. It is also used for platinizing glass, porcelain, and pumice stone.
== Synonyms and Related Terms ==
hydrogen hexachloroplatinate; acid platinic chloride; hexachloroplatinic acid; platinic chloride; platinum chloride
== Risks ==
* Inhalation and skin contact causes irritation and allergic reactions. 
* ThermoFisher:SDS
==Physical and Chemical Properties==
Soluble in water, ethanol, ether.
Composition 	H2PtCl6 - 6H2O
CAS 	16941-12-1
Melting Point 	60 C
Density 	2.431 g/ml
Molecular Weight	mol. wt. = 517.92
Boiling Point 	115 C
==Resources and Citations==
* Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
* The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: Entry 7684
* Michael McCann, Artist Beware, Watson-Guptill Publications, New York City, 1979
Category:Materials database
Chlorosulfonated polyethylene

== Description ==
A white spongy rubber. Chlorosulfonated polyethylene is made by crosslinking polyethylene with chlorine and sulfur. It is has a high resistance to acids, alkalis and abrasion. Chlorosulfonated polyethylene is often used to coat wires.
== Synonyms and Related Terms ==
polyéthylène chlorosulfoné (Fr.); polietileno clorosulfonado (Esp.); polietileno clorosulfonado (Port.) 
Examples: Hypalon® {Du Pont];
== Risks ==
* May form sulfur dioxide with degradation.
==Resources and Citations==
* MNRubber: Datasheets
* G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 306
* Pam Hatchfield, Pollutants in the Museum Environment, Archetype Press, London, 2002
Category:Materials database
Chlorotoluene

== Description ==
A colorless, low-viscosity solvent used for rubber and synthetic resins. It is also used as an intermediate in the manufacture of dyes.
[[[SliderGallery rightalign|chlorotoluene.jpg~Chemical structure]]]
== Synonyms and Related Terms ==
monochlorotoluene; alpha-chlorotoluene; benzyl chloride; chlorophenylmethane; chloromethylbenzene
== Risks ==
* Highly toxic by inhalation. 
* Strong irritation. 
* May be absorbed through the skin. 
* Combustible. Flash point = 67C 
* Burning produces toxic fumes. 
* Sigma-Aldrich: SDS
==Physical and Chemical Properties==
Miscible in ethanol, acetone, ether, benzene, carbon tetrachloride and heptane. Slightly soluble in water.
Composition 	CH3C6H4Cl
CAS 	100-44-7
Melting Point 	-43 C
Density 	1.0776 g/ml
Molecular Weight	mol. wt. = 126.6
Boiling Point 	179 C
== Resources and Citations ==
* G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 819
* Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
* Michael McCann, Artist Beware, Watson-Guptill Publications, New York City, 1979
Category:Materials database
Chlorpyrifos

== Description ==
Toxic, white granule crystals with a strong odor. Chlorpyrifos is an organophosphate type contact insecticide sold under the brand name of Dursban. Dursban is broad spectrum insecticide used to control cockroaches, chinch bugs, fleas, termites, ants, and ticks. It has been used in pet flea and tick collars.
[[[SliderGallery rightalign|chlorpyrifosir.jpg~FTIR|chlorpyrifosstr.jpg~Chemical structure]]]
== Synonyms and Related Terms ==
chlorpyriphosethyl; chloropyrifos (sp); O,O-diethyl O-3,5,6-trichloro-2-pyridyl phosphorothioate; Dursban [Dow]: Lorsban; Dowco 179; ENT 27311
== Risks ==
* Toxic by inhalation, ingestion and skin contact. 
* Corrosive to iron, copper and brass. 
* Discolors red dyes. 
* May leave deposits on nearby surfaces. 
* Combustible. 
* Cayman Chemical SDS
== Physical and Chemical Properties ==
Soluble in acetone, benzene, carbon disulfide, carbon tetrachloride, chloroform, diethyl ether, methylene chloride, xylene. Insoluble in water.
Composition 	C9H11Cl3NO3PS
CAS 	2921-88-2
Melting Point 	41-42 C
Density 	1.398 g/ml
Molecular Weight	mol. wt. = 350.6
== Resources and Citations ==
* Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
* Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
* The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983
* Lynda A. Zycherman, J.Richard Schrock, A Guide to Museum Pest Control, FAIC and Association of Systematics Collections, Washington DC, 1988
* J. Dawson, CCI Technical Bulletin, 'Solving Museum Insect Problems: Chemical Control' , Canadian Conservation Institute, Ottawa, No. 15
* Pam Hatchfield, Pollutants in the Museum Environment, Archetype Press, London, 2002
Category:Materials database
Chocolate marble

== Description ==
A dark brown marble with notable occurrences in the vicinity of Knoxville, Tennessee and in Ontario Canada. Chocolate marble has high strength, is translucent and polishes to a high gloss. It is commonly used as a building stone. Chocolate marble has been used in the Tennessee State Capitol building and the U.S. Capitol building.
== Synonyms and Related Terms ==
Dark Chocolate marble
==Resources and Citations==
* Dictionary of Building Preservation, Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996
* Olympus Microscopy Resource Center at http://www.olympusmicro.com/galleries/polarizedlight/pages/marblechocolatelarge.html (Accessed Sept. 17, 2005)
Category:Materials database
Cholesterol

== Description ==
A white, waxy sterol that occurs in all animal tissues. Cholesterol provides protection for the skin and nerve cells. It is obtained commercially from lanolin and is used as an emollient in cosmetics, hair conditioners, and pharmaceuticals.
[[[SliderGallery rightalign|Cholesterolf5.jpg~Chemical structure]]]
== Synonyms and Related Terms ==
cholest-5-en-3-ol; cholesterin; Cholesterin (Deut.); cholestérol (Fr.); colesterol (Esp., Port.); colesterolo (It.); cholesterol (Ned., Pol.); kolesterol (Sven.)
== Risks ==
* ThermoFisher: SDS
==Physical and Chemical Properties==
Soluble in ether, chloroform, benzene, pyridine, oils and fats. Insoluble in water. Gives an intense red color with rosaniline in chloroform solution.
Composition 	C27H45OH
CAS 	57-88-5
Melting Point 	148.5 C
Density 	1.067 g/ml
Molecular Weight	mol. wt. = 386.66
Boiling Point 	360 C (dec)
==Resources and Citations==
* Wikipedia: http://en.wikipedia.org/wiki/Cholesterol (Accessed Oct. 18, 2005)
* Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
* Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
* The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: Entry # 2256
* The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
* G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 881
Category:Materials database
Cholic acid

== Description ==
A bitter-tasting bile acid. Cholic acid is obtained naturally from ox bile extracts and commercially from cholesterol. It is used as a natural sequestrant and detergent. Bile acid can neutralize pH and solubilize many inorganic salts. The sodium salt of cholic acid is the primary component in oxgall.
[[[SliderGallery rightalign|cholic acid.jpg~Chemical structure]]]
== Synonyms and Related Terms ==
bile acid; ox gall; ox bile extract
== Risks ==
* Hygroscopic. 
* Fisher Scientific: MSDS
==Physical and Chemical Properties==
Soluble in acetic acid, acetone and ethanol. Slightly soluble in chloroform. Insoluble in water and benzene.
Composition 	C23H49O3COOH
CAS 	81-25-4
Melting Point 	198-199 C
Molecular Weight	mol. wt. = 408.57
==Resources and Citations==
* Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
* Richard C. Wolbers, Nanette T. Sterman, Chris Stavroudis, Notes for Workshop on New Methods in the Cleaning of Paintings, J.Paul Getty Trust, Los Angeles, 1990
* Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
* The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 2258
* The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
Category:Materials database
Cholinesterase

== Description ==
An enzyme whose function is to deactivate acetylcholine. Cholinesterase hydrolyzes the toxic acetylcholine into acetic acid and choline. It is found in the brain, heart, nerve cells and red blood cells. Some phosphorus-containing insecticides and nerve gases cause death by acting as cholinesterase inhibitors. Cholinesterase can be reactivated by the administration of atropine sulfate or pralidoxime iodide.
== Synonyms and Related Terms ==
acetylcholinesterase; cholin esterase
Category:Materials database
Cholla gum

== Description ==
A sticky exudation obtained from any of several Opuntia family cactus many of which are native to Mexico and the southwestern United States. Examples include:
- prickly pear cactus (Opuntia engelmannii)
- Jumping cholla (Opuntia fulgida)
== Synonyms and Related Terms ==
prickly pear cactus gum; prickly pear cactus (Opuntia engelmannii); Jumping cholla (Opuntia fulgida); goma de cholla (Esp.) 
== Additional Images ==
File:Oengelmanniv1.jpg|Pricly pear cactus Opuntia engelmannii
File:ochollaform.jpg|Chain cholla Opuntia fulgida)
File:Pricklypear_BG.jpg|Prickly pear cactus
==Resources and Citations==
* John S. Mills, Raymond White, The Organic Chemistry of Museum Objects, Butterworth Heineman, London, 2nd ed., 1994
* The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
* Virginia Tech Dendrology website at www.fw.vt.edu/dendro/dendrology/main.htm (accessed Oct. 3, 2005)
* Wikipedia: http://en.wikipedia.org/wiki/Prickly_pear (Accessed Oct. 3, 2005)
Category:Materials database
Chondrite

== Description ==
A stony meteorite. Chondrites are composed of small spherical granules embedded in a crystalline matrix. Stony meteorites account for about 80% of all meteorites. They contain pyroxenes and are classed accordingly as: enstatite, bronzite, or hypersthene. Chondrites have been dated using their strontium isotope ratios. 
See meteorite.
== Synonyms and Related Terms ==
none; Chondrit (Deut.); chondriet (Ned.)
Category:Materials database
Chosen-san shokuyo matsu no mi - left (377 L)

[[[SliderGallery rightalign|Uemura_10-15-2009_377.jpg~Normal]]]{| class="wikitable"
|-	
! scope="row"|Museum number
| 377
|-	
! scope="row"|Uemura number / title
| ; "Haze-some 25"
|-	
! scope="row"|Folder location
| 5th shelf
|-	
! scope="row"|Sample location
| left (377 L)
|-	
! scope="row"|Fiber type
| silk
|-	
! scope="row"|Color
| white
|-	
! scope="row"|Dyestuff (Japanese common name)
| 朝鮮産食用松の実 : Chosen-san shokuyo matsu no mi
|-	
! scope="row"|Dye (English common name)
| edible pine nut from Korea (Korean pine nut)
|-
! scope="row"|Dye (Botanical name)
| Pinus koraiensis
|-	
! scope="row"|Plant part
| nuts / dried
|-	
! scope="row"|Dyestuff extraction
| boiled in water
|-	
! scope="row"|Auxiliary agent in dye bath
| -
|-	
! scope="row"|Mordant
| lime
|-	
! scope="row"|Other auxiliary agent
| -
|-	
! scope="row"|Uemura's notes
| The Korean pine nuts are larger in their size than the Japanese ones.
|-	
! scope="row"|Uemura's date
| -
|}
Category:Uemura dye archive
Chosen-san shokuyo matsu no mi - right (377 R)

[[[SliderGallery rightalign|Uemura_10-15-2009_377.jpg~Normal]]]{| class="wikitable"
|-	
! scope="row"|Museum number
| 377
|-	
! scope="row"|Uemura number / title
| ; "Haze-some 25"
|-	
! scope="row"|Folder location
| 5th shelf
|-	
! scope="row"|Sample location
| right (377 R)
|-	
! scope="row"|Fiber type
| silk
|-	
! scope="row"|Color
| ochre
|-	
! scope="row"|Dyestuff (Japanese common name)
| 朝鮮産食用松の実 : Chosen-san shokuyo matsu no mi
|-	
! scope="row"|Dye (English common name)
| edible pine nut from Korea (Korean pine nut)
|-
! scope="row"|Dye (Botanical name)
| Pinus koraiensis
|-	
! scope="row"|Plant part
| nuts / dried
|-	
! scope="row"|Dyestuff extraction
| boiled in water
|-	
! scope="row"|Auxiliary agent in dye bath
| -
|-	
! scope="row"|Mordant
| iron
|-	
! scope="row"|Other auxiliary agent
| -
|-	
! scope="row"|Uemura's notes
| The Korean pine nuts are larger in their size than the Japanese ones.
|-	
! scope="row"|Uemura's date
| -
|}
Category:Uemura dye archive
Chroma

== Description ==
The perceived saturation, or intensity, of a color. Chroma is one of the three coordinates of the Munsell system of color notation. The maximum chroma, or 100 percent pure color, can have numbers of about 18-20. Weakly saturated colors can have chromas of about 2. The constant hue charts are prepared with regular progression from achromatic colors (black, gray, or white) at the left side of each chart to saturated colors on the right side. Chroma is an attribute in the CIE L*C*H* color model.
==Resources and Citations==
* Ralph Mayer, A Dictionary of Art Terms and Techniques, Harper and Row Publishers, New York, 1969 (also 1945 printing)
* 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
Category:Materials database
Chromatic aberration

== Description ==
A color distortion defect in a lens system. Chromatic aberration is the inability of a lens to bring varying wavelengths of radiation to a common point of focus. It is caused by refractive index variations. White light passing through a single lens will arrive at the image plane with the wavelengths from the blue end of the spectrum focused at a shorter distance than the wavelengths from the red end of the spectrum. The resultant image will have colored edges.
== Synonyms and Related Terms ==
Chromatische Aberration (Deut.); aberration chromatique (Fr.); chromatism
==Resources and Citations==
* Van Nostrand's Scientific Encyclopedia, Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976
* 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
* ASTM, Standard Terminology of Microscopy, Annual Book of ASTM Standards, Section 14, General Methods and Instrumentation, ASTM, E175, 75-78, May 1982
* Walter C. McCrone, John Gustave Delly, The Particle Atlas, W. McCrone Associates, Chicago, IV, 1972
* Theodore J. Reinhart, 'Glossary of Terms', Engineered Plastics, ASM International, 1988
Category:Materials database
Chromatic color

== Description ==
Any color except black, white and the simple grays (Mayer 1969).
== Synonyms and Related Terms ==
colore cromatico (cioè non acromatico: bianco, grigio, nero) (It.)
==Resources and Citations==
* R. Mayer, A Dictionary of Art Terms and Techniques, Harper and Row, New York, 1969.
Category:Materials database
Chromaticity

== Description ==
A quantitative color measurement of a material. Chromaticity is determined either by the dominant wavelength of the color along with its purity or by defining its three coordinates. Its chromaticity coordinates, obtained from tristimulus values, indicate the proportion of each of the three primaries in the measured color. A chromaticity diagram or color triangle is a plot of the three coordinates. 
See also tristimulus value.
== Synonyms and Related Terms ==
Chromatizität (Deut.); chromaticité (Fr.);
Category:Materials database
Chromatography

== Description ==
A set of techniques used to separate mixtures of compounds. Chromatography was invented in 1906 by M. Tswett who used it to separate chlorophyll from ground plant material. Each method uses column or plate with a stationary phase (liquid or solid) and a mobile phase (gas or liquid). Separation occurs due to the selective absorption and desorption of compounds on the stationary phase as the mobile phase moves past. Compounds attracted to (or similar to) the stationary phase will be absorbed part of the time causing them to elute slowly while compounds that are not retained will be carried along by the mobile phase and elute quickly. See also gas chromatography, liquid chromatography, size exclusion chromatography, ion chromatography, column chromatography, paper chromatography, and thin-layer chromatography.
== Synonyms and Related Terms ==
Chromatographie (Deut.); chromatographie (Fr.); 
Examples: gas chromatography; liquid chromatography; gel permeation chromatography; ion-exchange chromatography; column chromatography; paper chromatography; thin layer chromatography
Category:Materials database
Chrome

== Description ==
1) A common shortened form of chromium. Chrome is also used to refer to chromium alloys. 
2) An abbreviation used for color prints and dyes, such as Kodachrome.
==Resources and Citations==
* 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
Category:Materials database
Chrome-tin pink

== Description ==
A pastel reddish white ceramic pigment. Chrome-tin pink, or English pink, was developed about 1790 by a potter in Staffordshire. The color is produced when chromic oxide and stannic oxide fuse in the presence of lime. The color is dependent on particle size and is not always uniform. Pink can also be formed by the combination of chromium and zircon oxides. Chrome-tin pink was occasionally used as a pale pink artists color.
== Synonyms and Related Terms ==
English pink; potter's pink; rosa cromo-stagno (It.); rosa de estanho crómio (Port.)
==Resources and Citations==
* R. Mayer, The Artist's Handbook of Materials and Techniques, Viking Press, New York, 1981
* Ralph Mayer, A Dictionary of Art Terms and Techniques, Harper and Row Publishers, New York, 1969 (also 1945 printing)
* Robert Fournier, Illustrated Dictionary of Practical Pottery, Chilton Book Company, Radnor, PA, 1992
Category:Materials database
Chrome alum

== Description ==
1) Potassium chrome alum: a violet crystalline compound used in tanning, photography and dyeing textiles. 
2) Ammonium chrome alum: a green crystalline compound used as a mordant in dyeing.
== Synonyms and Related Terms ==
potassium chrome alum; ammonium chrome alum
==Resources and Citations==
* Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
* 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
Category:Materials database
Chrome dye

== Description ==
A dye that uses a chromium salt as a mordant. Chrome dyes most often use sodium dichromate or potassium chrome alum.
==Resources and Citations==
* Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
* 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
Category:Materials database
Chrome glue

== Description ==
An insoluble material prepared by mixing animal glue with ammonium dichromate, potassium dichromate, or chrome alum. It was used as a glass cement and as a waterproofing agent in the early 20th century.
==Resources and Citations==
* Thomas Gregory, The Condensed Chemical Dictionary, Reinhold Publishing, New York, 3rd ed., 1942
* Matt Roberts, Don Etherington, Bookbinding and the Conservation of Books: a Dictionary of Descriptive Terminology, U.S. Government Printing Office, Washington DC, 1982
Category:Materials database
Chrome green

== Description ==
A pigment mixture prepared with chrome yellow (lead chromate) and Prussian blue. Chrome green has been used since the early 19th century, primarily in house paints and industrial products. It is not used in artists paints.
== Synonyms and Related Terms ==
Pigment Green 15; CI 77600; verde cromo (Esp.); vert de chrome (Fr.); Zinnobergrün (Deut.); Chromoxydgrün (Deut.); prasino toy chromioy (Gr.); verde cromo (It.); chromaatgroen (Ned.); verde de crómio (Port.); cinnabar green; green vermilion; Victoria green; Prussian green; bronze green; Milori green; Brunswick green; nitrate green; royal green; zinnober green; oil green;
[[[SliderGallery rightalign|Chrome green, collodion slide Forbes (MFA 350), 532 nm.TIF~Raman (MFA)|f350sem.jpg~SEM|f350edsbw.jpg~EDS|Slide10 FC350.PNG~XRF (MFA)]]]
== Risks ==
* Toxic by inhalation, ingestion and skin absorption. 
* Human carcinogen and teratogen. 
* Suspected mutagen.
* Solomon Colors: SDS
==Physical and Chemical Properties==
* Turns blue with exposure to strong light or acids. 
* Turns dark orange with exposure to alkalis. 
* Individual blue and yellow particles are small and cannot usually be distinguish microscopically.
Density 	4.06 g/ml
Refractive Index	~2.4
==Resources and Citations==
* R. J. Gettens, G.L. Stout, Painting Materials, A Short Encyclopaedia, Dover Publications, New York, 1966 Comment: density=4.06, ref index=~2.4
* G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 611
* Reed Kay, The Painter's Guide To Studio Methods and Materials, Prentice-Hall, Inc., Englewood Cliffs, NJ, 1983
* Ralph Mayer, A Dictionary of Art Terms and Techniques, Harper and Row Publishers, New York, 1969 (also 1945 printing)
* Michael McCann, Artist Beware, Watson-Guptill Publications, New York City, 1979
* Dictionary of Building Preservation, Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996
* Book and Paper Group, Paper Conservation Catalog, AIC, 1984, 1989
* The Dictionary of Art, Grove's Dictionaries Inc., New York, 1996 Comment: "Pigments"
Category:Materials database