Color Index Name Code:
This is the official code given by the Color Index International for that particular pigment. The first 2 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.

PY = Pigment Yellow;
PO = Pigment Orange;
PR = Pigment Red;
PV = Pigment Violet;
PB = Pigment Blue;
PG = Pigment Green;
PBr = Pigment Brown;
PBk = Pigment Black;
PW = Pigment White;
PM = Pigment Metal

CI (Color Index) Pigment Name:
This is the official name given in the Color Index (third edition, 1997), or the name the first manufacturer or original patent holder has given that pigment, in a few instances where neither of the previous are available, I have used the actual chemical name. Where a pigment has no color index name, I have used the traditional historic name or the mineral/chemical names.

Common, Historic and Marketing Names:
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 name but merely a collection of names that are in common usage or have been used. They have been culled (in order of importance) from paint manufacturer and supplier literature, The Color Index, Third edition (1997), Historical Books on pigments and art (see Free Art e-Books), Artist manuals and handbooks (see the bottom of the Pigment Database's main page for a complete list of reference works), various dictionaries and encyclopedias (old and new), and various web sites in particular AMIEN.org, Dick Blick Artist Supply, Handprint.com, Natural Pigments, Kama Pigments, Sinopia Pigments, PCImag.com and Kremer Pigments, along with the paint, chemical and pigment manufacture sites.
Marketing names given by paint manufacturers are often misleading, deceptive or descriptive of the color and not the actual pigment. Where there is a common historic name associated with that pigment I have used "GEN" to denote the generic common historically accepted name of that particular pigment. When a manufacturer has used a common historical name for a pigment that is not the accepted traditional historic pigment name, I have indicated it with the "(hue)" designation.

C.I. (Color Index) Pigment # (number):
These are the chemical composition number given that pigment by the Color Index International (see Colour Index Number Categories here)

Chemical Composition:
These are the basic chemical names, or mineral names along with chemical composition. Where I can fine them, I have included CAS numbers. Sometimes multiple names are given because chemical names can be stated in different ways or the pigment is a group of chemicals rather than a single one. I have not included detailed chemical descriptions or analyses but only basic information that should help you find further information. I have included references designated with "(Ref)" where further information can be attained.

Color Description:
This is a general attempt to explain the hue 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. I have not in all cases used any of the attempted means of standardizing color descriptions for this, but where the pigment is included in the Color Index International Pigments and Solvent Dyes (The Society of Dyers and colourists, third edition), I have used that description, when not, I have used other reference sources in particularly manufacturer or supplier literature.

Opacity- Transparency*: 
The opacity and transparency is only a general reference, where available, i have used the Color index's designation or manufacturers literature to arrive at this figure. Many pigments exist in both transparent and opaque versions, or can be manipulated by the paint or pigment manufactures for a particular purpose. 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**:
The light fastness rating is only a general reference, where available i have used the ASTM or manufacturers literature to arrive at this figure. The ASTM has not rated all pigments, so this rating in this database will not always be the ASTM rating but a rating culled from other sources, most importantly manufactures literature. The ASTM ratings have a 5 increment scale and the blue-wool scale is 8, in this database lighfastness ratings have been condensed or averaged to a less specific 4 designations. I can can not cover every possible paint, binder, or pigment formulation in this chart as it would take too much time and space; there are so many variables as to make this designation, in this database, of only marginal use. In particular the quality of the actual pigment manufacture has much influence on a pigments fastness to light, heat and other chemicals. Additives, binder, and many other factors all have a influence on light fastness or fastness to other environmental influences. 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. The only way to be sure, is to make your own tests on the paint or pigment you have. Reference the following: (ASTM D4303 - 10 opens new window); (AMIEN.org Thread - opens new window)
 
I = Excellent,
II = Good,
III = Poor,
IV = Fugitive/Very Poor

Oil Absorption: is in ml/100mg
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).

When the specific numbers are unavailable:   H = High,   M = Medium,   L = Low

Toxicity***:
The hazardous properties is a general designation of a possible hazard. It is assumed intelligent people will use at least ordinary care when handling all paints or pigments. The designation has been arrived at from, in most cases, the manufacturer's literature, MSDS sheets at the Oxford University Chemical Laboratory., or the City of Tucson's Environmental Management Division's searchable database of Health & Safety in the Arts. All paints and especially dry pigments can be hazardous if carelessly handled, but if handled properly with common sense all but the most dangerous can be used safely.

A = Low hazard, but do not handle carelessly;
B = Possible Hazard if improperly or carelessly handled;
C = Hazardous, use appropriate precautions for handling mildly toxic substances; 
D = Extremely Toxic, only attempt working with this pigment (especially the dry form) in laboratory like conditions and with proper safety equipment (see "Prudent practices in the laboratory: handling and disposal of chemicals" at google books opens new window; or PDF format here);

Side Notes:
These are typically interesting things I have read, or information collected on a pigment that may be worth further study. 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. References (Ref) may be provided.

(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 source of the information I have given. or 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 reference, possible typo or other discrepancies in the manufacturer or other reference documentation. Further study is needed to clarify.

†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 = Becomes more Transparent;  Lightens = Loses chroma but maintains relative transparency or opaque character;  Whitens = Becomes lighter and more opaque;  Darkens = Becomes darker but retains hue;  Dulls = Loses chroma towards neutral;  Blackens = Turns very dark or black losing chroma;  Hue shift = Changes hue towards a different color