Color Index Generic Name:   Key Top ^ Page Top^
This is the C.I. Generic Name (abbreviated) given by the ASTM and Colour Index International (CII) for that pigment. The first 2 or 3 letters describe the general pigment color and the number is the individual pigment identifier. N/A (not applicable) means that pigment has not been given a color index name or number.

The CI (Color Index) Common Pigment Name:   Key Top ^ Page Top^
In this database the common name is the name given in the Color Index (third edition, 1997) by the Color Index International published by the Society of Dyers and Colourists and the American Association of Textile Chemists and Colorists, and are also used by the ASTM International, American Society for Testing and Materials.

When the Colour Index (3rd edition) has not specified a name, I have used the name that the first manufacturer, inventor or original patent holder has given that pigment. In the case of ancient pigments, historic pigments, minerals or other odd pigments, I have used the most commonly used traditional historic, mineral or chemical name as determined by my research.

Common, Historic and Marketing Names:   Key Top ^ Page Top^

These are the various names that have been used for that pigment whether or not it is the correct usage. This is NOT an endorsement of any particular name, but merely a collection of names that are in common usage or have been used in the past according to historic pigment books & references, paint sales literature, and pigment manufacturers references. They have been collected (in order of importance) from

1.) Paint manufacturers, pigment manufacturers and/or other pigment supplier literature;

2.) Various web sites (an incomplete list, in no particular order): AMIEN.org is unfortunetly gone, but the good news is the MITRA (Materials Information and Technical Resources for Artists) has taken up the cause, Handprint.com; WetCanvas.com; Blick Art Materials Artist Supply Pigment Information; Boston Fine Arts CAMEO Conservation & Art Materials Encyclopedia; Kremer Pigments; Natural Pigments; Kama Pigments; Sinopia Pigments; PCImag.com; WebExhibits.org "Pigments through the Ages Online Museum"; and along with internet forums on art and painting, web sites of paint manufacturers, paint suppliers, chemical manufacturers and pigment manufacturers;

3.) The Color Index, Third edition (published by the Colour Index International, 1997);

4.) Historical books on pigments, oil painting, watercolor painting and other art forms (see Free Art e-Books);

5.) Artist manuals and handbooks (see the bottom of the Pigment Database's main page for a complete list of reference works);

6.) Various dictionaries and encyclopedias (both historic and contemporary, online and physical).

(hue):
When a manufacturer has has used a common historical name for a pigment that is not the accepted traditional historic pigment name and has not clearly indicated it to be a hue or substitute, I have indicated it with the "(hue)"* in parenthesis. For example calling/naming a paint made with Phthalocyanine Blue as "Egyptian Blue", "Smalt" or "Cobalt Blue".

* In order to stay within ASTM specification D 4302-05, manufactures are encouraged to use the word "hue" when the paint or pigment marketing name is not the real name of a paint or a pigment. 'Substitute', 'tone' or prefixed with words like 'Permanent' could be also considered acceptable means of indicating a hue substitute for the actual color. The ASTM specifications are voluntary and no one enforces them. Also because of language differences, changes in the paint or pigments common identification and because of contemporary usage (often perpetrated by manufacturer's incorrect color marketing names), and last but not least - the sheer multitude of historically used paint names for any given paint\pigment, it's nearly impossible to prove or say a manufacturer of art materials is being purposely deceptive.

C.I. Constitution Number or Colour Index Constitution Number (chemical composition):   Key Top ^ Page Top^

These are the chemical constitution numbers given that pigment by the Color Index International published by the Society of Dyers and Colourists and the American Association of Textile Chemists and Colorists, and are also used by the ASTM International, American Society for Testing and Materials. Each of the numbers in the "Colour Index Constitution Number" has a specific chemical or compositional meaning; for more information see the Colour Index Number Chart or go to the Color Index International and ASTM, American Society for Testing and Materials web sites (these links open in a new window)..

Chemical Composition:   Key Top ^ Page Top^

These are the basic chemical names, or mineral names along with chemical composition and sometimes, when available, manufacturing details. I have also included CAS numbers, when I can fine them. Sometimes multiple names are given because chemical names can be stated in different ways, the different chemical names can be an indication of the different manufacture methods. Very often a pigment can be a group of related compounds rather than one specific chemical. I have not included detailed chemical descriptions or analyses, but only basic information that should help you to find further information. I have included references designated with "(Ref)" where further information can be attained.
Adulterants, extenders and other additives may be added to artistic paints & pigments to improve the paint rheology, transparency, wetting and\or drying time. Often inert pigments, extenders and fillers are added to the color pigments in student grade paints or to modify paint pigments with overly strong tinting strength, i.e. the Phthalocyanine Blues and Greens. These extra ingredients are rarely listed of the label.

Color Description:   Key Top ^ Page Top^

This is a general attempt to explain the color, hue and value in plain English. The perception of color is as individual as the the people viewing it and any such description can not be completely accurate, but merely give a general idea of the what color looks like to the average person. Many pigments have a range of shades and hues. This range in hues, even in the same pigment, can be due to many things such as different manufacturing processes, chemical modifiers added during production, calcining temperature and length of time, milling time, particle size, exact chemical composition, in lake pigments the base the dye is fixed on, additives, binder , etc, etc.. In most cases, i have not used any of the attempted means of standardizing color descriptions for this (such as the Munsell system), but where the pigment is included in the Color Index International Pigments and Solvent Dyes (The Society of Dyers and Colourists, third edition 1997), I have used that description, when there is no color hue description in the Color Index, I have used other reference sources, in particularly, manufacturer or supplier literature and personal judgement.

† = Effects of long term light exposure are given when known, this may allow an artist to anticipate color changes and possibly use them as an advantage. These effects are all relative to the pigments inherent light fastness and may take decades or even centuries in museum conditions to be visible.

Fades = Loses chroma and becomes more Transparent
Lightens = Loses chroma but maintains relative transparency or opaque character;
Whitens = Becomes lighter towards white and more opaque;
Darkens = Becomes darker but retains hue;
Dulls = Loses chroma towards neutral but maintains the relative tone value;  
Blackens = Becomes darker moving towards black losing chroma;  
Hue shift = Changes hue towards a different color

Opacity - Transparency:   Key Top ^ Page Top^

This designation is only a general reference to the most common encountered opacity or transparency inherit to the pigment. In paint formulations, the transparency of a pigment can change due to what is used as the painting medium or binder (i.e., oil color, watercolor, encaustic, acrylic, etc.). There are many pigments that are opaque in watercolor but transparent or semi-transparent in oil paints. The transparency of a paint or pigment can often be manipulated by the manufacturing process for a particular purpose and so some pigments are available in transparent and opaque versions. The addition of inert pigments or other modifiers can also change the perceived transparency of a paint formulation or pigment.
When available, i have used the Color index's designation or manufacturers literature to arrive at this figure. When the Color Index description is unavailable i have arrived at a general figure by manufacturer literature or personal experience. A general designation such as given will not always be the case in any particular formulation.
 
1 = Opaque,
2 = Semi-Opaque,
3 = Semi-Transparent,
4 = Transparent

Light Fastness Rating:   Key Top ^ Page Top^

The light fastness ratings can only be a general guide, the only reliable way to confirm lightfastness in your paints and your preferred medium is to make your own tests on the paint brand or pigment you have. I have used the ASTM rating when possible, but The ASTM has not rated all pigments, and stopped rating pigments entirely sometime in the late 90's early 2000's. The ASTM stopped rating pigments because it is not possible to test every pigment & shade of pigment in every binder and have the results mean anything in the real world. The ASTM now advises that the manufacturer of a brand make their own tests according to the ASTM D4303-10 guidelines and submit them to the ASTM for approval. However I don't know of any company that has done this. The ASTM lightfastness ratings were never a perfect way to determine light fastness of a pigment that has been used in a unique paint brand formulation.

For the reasons above, the rating in this database, will not always be the official ASTM rating but a rating culled & averaged from other sources such as individual paint brand ratings, my own personal tests, tests results in other sources such as books, artist forums and websites like Handprint.com and/or pigment manufactures literature and blue wool scales. The ASTM ratings have a 5 increment scale and the blue-wool scale is 8, in this database I will use the same scale as the ASTM for light fastness ratings, even though they may not be ASTM ratings. Very often, pigments in tints are less light fast than in full masstone and this should be taken into account when determining if a pigment or paint will meet your needs. ASTM ratings only have a rating for full shade or masstone. I can not cover every possible paint, binder, or pigment formulation in this chart as it would take too much time and space. Many factors can influence the light fastness of any particular paint formulation, for instance, the quality of the actual pigment manufacture and amount & type of impurities has much influence on a pigments fastness to light. Particle size, extenders, binder, and additives play a role in light fastness too. Most artist paint brands and the ASTM do not test for the effects of heat, moisture, pollution or other environmental factors. Whether a paint is watercolor, oil color, tempera, etc. has an effect on light fastness. Varnishes and other treatments to the painting surface or support can have an influence too. As a general rule (but not always the case) oil, alkyd and acrylic binders add some degree of protection and will be slightly more light fast than watercolors.Reference the following: (ASTM D4303 - 10, Standard Test Methods for Lightfastness of Colorants Used in Artists' Materials, or ASTM D01.57, the Subcommittee on Artists' Materials doc here, opens new window);

Blue Wool Scales will be added when found, but be aware that most of these will be tests performed by the pigment manufacturer on a single formulation that could be results from melamine (Plastic), alkyd, oil, water or acrylic emulsions and may not be indicative of it's use in all / or any particular artist paint brand or binder.

ASTM scale or equivalents (see the table below for conversion to & from the Blue Wool Scale):

I = Excellent, should last over 100 years in Museum conditions
II = Very Good, should show no signs of change for 50–100 years in Museum conditions
III = Fair, should show no signs of change for 15–50 years in Museum conditions
IV = Poor, should last 2–15 years in Museum conditions
V = Fugitive or very poor, will show changes in 2 years or less in Museum conditions

BWS = Blue wool scale

7-8 = ASTM I, Excellent
6 = ASTM II, Very Good
4-5 = ASTM III, Fair
2-3 ASTM IV, Poor (Impermanent)
1 = ASTM V, Very Poor (fugitive)*

*When known, blue wool scale ratings will be given for tints in the following format: Full;1/2 tint/;1/4 tint (i.e. Cadmium Red would be 8;8;8 with excellent light fastness in all tints). Note: these may from tests on a single formulation or pigment brand, and may not be valid for other brands or binders.

Oil Absorption: is given in g/100g or grams of oil per 100 grams of pigment   Key Top ^ Page Top^
or as H, M, L (see below)

The oil absorption figure has been arrived at from the pigment manufacturer's literature or artist reference sources (see the bottom of the Pigment Database's main page for a complete list of reference works). The higher the oil absorption, generally, the longer it will take to dry when used in oil painting. The addition of driers, siccatives, retardants and other additives can effect the drying time of any specific formulation, or they can be added by the artist to speed up or slow down the drying of oil paints. In some literature the oil absorption rate is given as ml/100g, although not technically the same as g/100g, for the purposes of this database they are close enough.

Depending on the specifications i have available I may also use the following designations:
H = High;   - These pigments absorb a lot of oil.
M = Medium;    - absorbs a medium amount of oil, and generally will have an average drying or cure rate
L = Low;    - absorbs very little oil, usually very fast driers

Under this heading will be a general designation of a possible hazard. It is assumed intelligent people will use at least ordinary care when handling all paints or pigments. A rating of 'A' in this database, does not mean the pigment is totally harmless, but only that there is low toxicity under reasonable use, it does not mean you can eat it, even so called "Food Colors" are not meant to be used in large quantities and may have unknown side effects or allergic reactions. There are no artists' pigments that are made to 'food grade' or 'pharmaceutical grade' standards, so even if a certain coloring is considered non-toxic, it does not mean it's OK to ingest or carelessly handle. The designation here has been arrived at from, in most cases, the manufacturer's literature, art books and art reference works (see the bottom of the Pigment Database's main page for a complete list of reference works, MSDS sheets, the EPA manual: Environmental Health & Safety in the Arts: A Guide for K-12 Schools, Colleges and Artisans (full PDF here), The Art & Creative Materials Institute, Inc. (ACMI), The Health and the Arts Program - Great Lakes Centers at the University of Illinois at Chicago School of Public Health (UIC SPH), The American Institute for Conservation of Historic & Artistic Works has a collection of articles on art safety, The Consumer Product Safety Commission's Art and Craft Safety Guide (PDF, 250 KB) and Art Materials Business Guidance.

All paints and especially dry pigments can be hazardous if carelessly handled, but, if handled properly with common sense all but the most dangerous pigments can be used safely.

WARNING: Always use a dust mask when working with any dry pigments. Work in a separate area of your studio away from children, pets or other living things. Do not smoke, eat or drink around any art materials. Dispose of all waste materials in an environmentally friendly and safe way.

A = Low hazard, but do not handle carelessly; Do not ingest; Avoid dust & spray.
B = Possible hazard if carelessly handled, ingested in large amounts or over long periods of time; Do not ingest; Avoid dust & spray.
C = Hazardous, use appropriate precautions for handling toxic substances, especially if working with the dry powder; Do not ingest; Avoid dust & spray.
D = Extremely Toxic, only attempt working with these pigments (especially the dry form) in laboratory like conditions with proper safety equipment (see "Prudent practices in the laboratory: handling and disposal of chemicals" at google books opens new window); or the PDF - Booklet Safe Handling of Colour Pigments Copyright © 1995: BCMA, EPSOM, ETAD, VdMI - link from VdMI

The Side Notes Column:   Key Top ^ Page Top^

These are typically interesting things I have read, or information collected on a pigment that may be worth further study. Please remember that they are NOT statements of absolute fact. Many pigment qualities are rumors, old wife's tales and misconceptions repeated over and over until they accepted as fact without any scientific proof. I will include references (Ref) for further info.

Miscellaneous:

(hue) = When the word "hue" in in parenthesis (hue), it refers to a hue color not designated on the label, when the word "hue" is not in parenthesis is part of the pigment name as per ASTM guidelines.

(Ref) = A link to a reference source. This may be the reference source of the information that I have given, or just a link to more detailed information.

? = a question mark next to a name, note, or data code indicates that it may or may not be correct information due to conflicting information, questionable references, possible typo or other discrepancies in the manufacturer or other reference documentation. Further study is needed to clarify.