Natural Pigments Learning Center
How to choose and understand dry artist pigments
Learn how pigment identity, chemistry, physical properties, permanence, and medium compatibility affect color and handling. Use this guide to interpret our Pigment Specifications table and the complete technical information on individual pigment pages.
Begin Here
Natural Pigments provides three levels of information. The Pigment Guide explains how to make informed choices, the Specifications table supports catalog-wide comparison, and individual pigment pages provide the complete product-specific technical record.
Use this page to understand pigment terminology, compatibility, physical and optical properties, permanence, safe handling, and paint-making considerations.
Best for learning what the data mean and deciding which properties matter for your medium or technique.
Use the comparison table to filter pigments by color family, recommended medium, pigment type, chemical family, Colour Index, particle size, hardness, oil absorption, density, refractive index, and safety information.
Open a pigment page for the complete product-specific record, including available ASTM lightfastness information, opacity, Standard Depth, detailed composition, synonyms, permanence ratings, warnings, SDS documents, sizes, and purchasing options.
Important: A blank or unavailable specification should not be interpreted as zero or as evidence that the property is unimportant. Some technical data are not available uniformly across natural, historical, and modern manufactured pigments.
Start with the Application
Pigments do not behave identically in every binder. Wetting, transparency, texture, settling, drying, chemical stability, and permanence may change according to the painting medium, pigment concentration, application thickness, and working method.
In oil paint, consider oil absorption, texture, drying effects, tinting strength, opacity, transparency, and the amount of binder required to produce a sound paint film.
In watercolor and gouache, wetting, particle size, granulation, sedimentation, transparency, staining, and behavior in thin applications become especially important.
Egg tempera benefits from pigments that disperse well in a relatively lean aqueous emulsion and can be applied in thin, controlled layers.
Strongly alkaline systems require pigments that remain stable in lime, cement, or related mineral binders.
Pigments used in heated wax systems must tolerate the working temperature and disperse effectively in molten wax.
Waterborne polymer systems require effective wetting and dispersion. Chemical stability and migration resistance may also affect performance.
Selection principle: Begin with pigments recommended for the intended binder or technique, then compare their color, permanence, physical properties, handling, and safety information.
Identify the Material
A pigment may have a common name, historical name, mineral name, trade name, chemical description, and Colour Index designation. These identifiers are related, but they do not provide identical information.
The Colour Index Generic Name helps establish the general identity of a pigment. It is useful when comparing labels, technical literature, and products from different suppliers.
It does not establish every property of a particular commercial pigment.
Two pigments identified by the same Colour Index designation may still vary in hue, transparency, strength, texture, oil absorption, and dispersion behavior.
Use the Colour Index to confirm the general pigment category, then review the individual product page to understand the specific material being offered.
Understand the Chemistry
Pigments are finely divided, generally insoluble colorants dispersed in a binder. They may be single compounds, natural mineral mixtures, or engineered composite particles. Their compatibility and behavior can vary according to the medium and environment.
Some pigments have a relatively well-defined chemical identity, although commercial grades may still vary in particle size, crystal structure, purity, surface treatment, or manufacturing process.
Individual pigment pages may provide a chemical name, formula, CAS number, Colour Index designation, and other identifying information where applicable.
Natural earth pigments commonly contain mixtures of iron oxides, manganese oxides, clay minerals, silica, carbonates, and other naturally occurring constituents.
Variation in source and mineral composition can contribute to differences in hue, undertone, transparency, texture, density, and oil absorption.
Modern pigments may be manufactured to control crystal form, particle-size distribution, color strength, transparency, durability, or dispersibility.
Pigment families include synthetic iron oxides, mixed-metal oxides, ultramarines, cobalt pigments, quinacridones, phthalocyanines, and many other inorganic and organic systems.
Some effect pigments consist of a substrate coated with one or more materials to produce pearlescent, metallic, interference, or other optical effects.
These materials should be evaluated according to their full structure rather than treated as a single conventional pigment compound.
The Specifications table provides a concise Pigment Family / Chemistry field for filtering and comparison.
Individual pigment pages provide the more complete record where available:
Compare Primary Specifications
Physical-property data help explain why pigments of similar color can behave very differently during paint making and application. The Specifications table allows selected primary properties to be compared across the pigment range.
Particle-size data may describe a typical value, range, median, or measured distribution. It does not necessarily represent isolated primary particles because pigments often contain aggregates or agglomerates.
Particle size can influence:
Mohs hardness is an approximate measure of a mineral’s resistance to scratching. It can help indicate the abrasiveness of a pigment during mulling, brushing, or mechanical processing.
Natural pigments may contain several minerals and therefore may require a range or qualified value rather than one exact number.
Hardness does not by itself measure how difficult a pigment is to wet or disperse.
Oil absorption reports the amount of oil needed to form a specified paste consistency under a defined test method, generally expressed as grams of oil per 100 grams of pigment.
It can help indicate:
The value is not an exact formula for finished artist oil paint.
Density or specific gravity describes the mass of pigment relative to its material volume. It is different from the loose bulk volume occupied by powder in a jar.
Density can affect:
Refractive index describes how strongly light is refracted within a material. The difference between the refractive indices of the pigment and binder contributes to light scattering and opacity.
Actual opacity also depends on particle size, concentration, dispersion, film thickness, particle shape, and the particular binder.
Where supplied on an individual product page, specific surface describes the surface area per unit mass. It is influenced by particle size, shape, porosity, aggregation, and surface texture.
A high specific surface may increase binder demand and influence wetting or dispersion, but it should not be interpreted simply as “very finely ground.”
Comparing values: Technical values may be typical rather than guaranteed, and data from different measurement methods are not always directly comparable. Natural materials may also vary by deposit or batch.
Evaluate Appearance and Handling
Numerical specifications help characterize a pigment, but artists also need to understand its appearance and working qualities in a binder. These observations are provided on individual pigment pages where applicable.
Mass tone is the appearance of a pigment in a concentrated or relatively thick paint layer.
Undertone is revealed when the pigment is applied thinly, dispersed more completely, or mixed with white.
Two pigments that appear similar in mass tone may show very different undertones and mixing behavior.
Opacity is related to the pigment’s refractive index, but refractive index alone does not determine how opaque the pigment will appear in paint.
Observed opacity depends on:
Opacity or transparency classifications are provided on individual pigment pages.
Tinting strength describes how strongly a pigment changes the color of a mixture. A high-strength pigment may require only a small amount to dominate a mixture.
High tinting strength is not automatically a sign of superior quality. Some artists deliberately select weaker or more moderate pigments for controlled mixing and subtle transitions.
Particle size, density, shape, aggregation, and natural mineral composition can produce smooth, granular, sedimentary, or textural effects.
These differences are especially visible in watercolor, tempera, fresco, and thin oil applications.
In watercolor, some pigments penetrate or adhere strongly to the paper and are difficult to lift, while others remain more readily removable after drying.
Staining is influenced by particle size, pigment chemistry, dispersion, paper sizing, and the formulation of the watercolor.
In oil paint, certain pigments accelerate drying, while others may dry slowly. Pigment chemistry, surface area, oil absorption, binder, additives, and paint thickness all influence drying behavior.
Product-specific application notes should be reviewed when drying behavior is important.
Do not infer appearance from one number: Refractive index, particle size, density, or oil absorption can help explain behavior, but no single specification completely predicts how a pigment will look or handle in paint.
Plan for Longevity
Lightfastness describes resistance to color change caused by light exposure. Permanence is broader and may also include chemical stability, binder compatibility, resistance to environmental conditions, and behavior in mixtures or layered applications.
Where applicable and available, ASTM lightfastness information is provided on individual pigment pages rather than in the primary Specifications table.
A rating should be interpreted in the context of the tested medium, pigment concentration, exposure method, and source of the data.
Do not assume that a rating reported for one binder automatically describes every use of the same pigment in another binder.
Other relevant properties can include:
Individual pigment pages provide available lightfastness, permanence, resistance, and compatibility information for that specific product.
When information is incomplete or the application is unusual, prepare a representative test using the intended binder, concentration, substrate, and exposure conditions.
Interpret Color-Strength Data
Standard Depth provides a controlled way to evaluate pigment color strength and appearance at defined concentrations or reductions. Where available, Standard Depth information is provided on individual pigment pages rather than in the primary comparison table.
A strong pigment generally requires less pigment to reach a comparable visual depth.
Standard Depth results should be interpreted with the test method, binder, white pigment, concentration, and reduction procedure in mind.
Values from different test systems should not be assumed to be directly comparable.
Color strength does not by itself determine quality, permanence, opacity, compatibility, or suitability for a particular technique.
Practical use: Standard Depth reductions are particularly useful when comparing pigments for pale tints, flesh colors, skies, glazing mixtures, and other applications in which undertone becomes more important than mass tone.
Work Cleanly
Dry pigments are fine powders. The primary general studio concern is avoiding airborne dust, inhalation, ingestion, and unnecessary skin contamination. Some pigments require additional precautions because of their specific composition.
Review the product label and Safety Data Sheet before use, particularly for pigments containing lead, cadmium, chromium, cobalt, manganese, crystalline silica, or other specifically classified substances.
Use appropriate gloves, protective clothing, ventilation, and NIOSH-approved respiratory protection when required by the SDS, exposure assessment, or working conditions.
Heating pigments can introduce additional risks. Review the pigment-specific information before using a pigment in encaustic, ceramic, industrial, or other heated processes.
Information hierarchy: The Specifications table provides a concise safety summary. The individual pigment page and SDS provide the product-specific warnings and handling requirements.
Make Paint from Dry Pigment
Successful paint making requires more than combining pigment and binder. The pigment must first be wetted, then dispersed sufficiently to develop consistent color, texture, and stability.
Wetting occurs when the liquid displaces air at the pigment surface. Pigments vary greatly in how readily they are wetted by oil, water, wax, or polymer binders.
Some hydrophobic organic pigments and carbon pigments may be difficult to wet with water alone and may require a compatible wetting or dispersing procedure.
Dispersion separates and distributes agglomerated pigment particles through the binder. Effective dispersion improves color development, consistency, and stability.
Excessive or inappropriate grinding can alter the desired texture of some coarse, historical, or naturally granular pigments.
A glass muller distributes pigment through a binder and breaks down loose agglomerates. Hand mulling does not ordinarily reduce the pigment’s primary manufactured particles to a fundamentally smaller size.
Add binder in small increments. Excess binder can produce an overly fluid or overbound paint, while too little binder can leave a dry, crumbly, or inadequately bound paste.
Dense pigments may settle in fluid systems. Poor wetting or incompatible surface interactions can also cause flocculation, in which particles form loose structures that reduce color strength, uniformity, or storage stability.
Paint-making procedures vary according to:
Follow medium-specific instructions rather than assuming that all pigments can be wetted or dispersed using the same liquid and procedure.
Begin with a small amount of pigment and binder. Record the proportions, working time, dispersion method, and resulting consistency.
Evaluate the paint after application and drying before preparing a large batch.
Put the Information Together
Use the following sequence to move from a broad color need to a technically appropriate pigment for your medium and working method.
Begin by eliminating pigments that are unsuitable for the binder, alkalinity, heat, exposure conditions, or application process.
Narrow the catalog to white, yellow, orange, red, violet, blue, green, brown, black, gray, metallic, pearlescent, or another relevant visual category.
Decide whether you need an opaque or transparent pigment, strong or moderate tinting strength, smooth or granular texture, bright or muted hue, or a modern or historical color character.
Use the Pigment Specifications table to compare pigment type, chemistry family, Colour Index, particle size, hardness, oil absorption, density, refractive index, medium suitability, and safety information.
Check the available ASTM lightfastness information, opacity, Standard Depth, detailed composition, synonyms, permanence ratings, application notes, warnings, and SDS.
Prepare a representative test when the binder is unusual, the work is technically demanding, the application is very thin, the pigment will be heated, the environment is strongly alkaline or acidic, or several pigments and additives will be combined.
Keep test records: Note the pigment, lot or source, binder, proportions, additives, substrate, application thickness, drying conditions, and observations. These records make future comparisons much more useful.
Continue Your Search
Compare primary data, browse pigments by application, or open individual product pages for complete technical information.
Filter the pigment range by color, medium, chemistry, Colour Index, physical properties, and safety information.
Begin with pigments selected for oil, watercolor, tempera, fresco, encaustic, acrylic, or another painting method.
Explore the complete dry-pigment catalog and open individual pages for complete specifications, application notes, SDS documents, and purchasing options.
Understand your pigments—composition, permanence & properties
Use this page to decode the technical data behind our dry pigments—so you can compare materials confidently and choose the right color for your medium and method.
Pigments often have multiple historical and trade names. Use the identifiers below to confirm you’re working with the pigment you intend—and to compare like-for-like across brands and references.
Use the Colour Index to confirm identity, then look at composition and properties to understand performance.
| Pigment name | Ultramarine Blue (example) |
| Colour Index | PB29 |
| Chemical identity | Sodium aluminosilicate sulfur complex (composition varies by manufacturer) |
| Why it matters | CI confirms you’re comparing the same pigment; properties explain transparency, strength, and handling. |
Explore pigments by category and compare options quickly:
If you’re new to pigment selection, this page helps you interpret the technical fields used across our pigment listings.
These fields describe what the pigment is (chemically and physically) and how it’s typically identified in technical references and safety documents.
Lightfastness indicates resistance to fading under light exposure. Permanence also includes chemical stability and compatibility under real painting conditions (binder, thickness, mixed pigments, and environment).
When listed, ASTM lightfastness uses Roman numerals (I = excellent, V = very poor) and may be reported by medium (oil, acrylic, watercolor).
Physical properties influence handling, dispersion, texture, transparency, and how much binder is required. These fields are especially useful when making paint or adjusting working properties.
Indicates how much oil (or binder) a pigment requires to form a workable paste. Higher oil absorption generally means more binder is needed and may affect gloss and drying behavior.
Density affects settling and handling. Bulk volume helps estimate storage volume and batch size by weight-to-volume conversions (useful when preparing paint or dispersions).
A measure related to particle fineness and surface area. Higher surface area often increases binder demand and can affect opacity, tinting, and dispersion effort.
SD (Standard Depth) is a standardized method to describe color strength and tinting behavior in controlled reductions with a white pigment (often Titanium Dioxide). When you see reductions such as 1/3 SD or 1/25 SD, they indicate performance at specific dilution levels.
Reduction ratios are the measured mixing ratios used to reach specific standardized depths. They help compare tinting strength and hue stability between pigments.
Dry pigments are fine powders—treat them with care. The main studio risk is airborne dust. Some pigments contain heavy metals or other hazardous components and require extra precautions.
Pigments containing metals such as lead, cadmium, chromium, cobalt, and manganese may require heightened precautions depending on form and exposure route.
If you have questions about safe handling practices, contact us for guidance.
Making paint from pigment is straightforward, but technique matters: proper wetting and dispersion improve color development, consistency, and stability.
Learn a practical, step-by-step method: add oil gradually, mix thoroughly, mull to develop smoothness, then adjust consistency by small additions of pigment or oil.
Wet pigment with distilled water, form a paste, mull for full dispersion, then incorporate your binder (gum arabic, egg yolk, glue, etc.).
Use these guides to choose pigments for your medium and to interpret the fields in the technical table across products.
