Decoding Your Paint: A Practical Guide to Oil Paint Characteristics

By R.R. Christensen

When it comes to oil painting, the materials you choose have a profound effect on the outcome of your work—not just in color, but texture, drying time, durability, and archival quality.  For many artists, the composition of individual pigments remains a mystery. The labels are covered in symbols, pigment codes, and technical information, and without guidance, it’s easy to choose paints based on color names alone.

Learning to read a paint label and understand the characteristics of oil paint allows an artist to mix colors more predictably, plan layering with confidence, and ensure your work will stand the test of time. This guide will help you interpret the information printed on the label or published on the manufacturer’s website and make smart informed choices in your studio practice.

How to Read a Tube of Oil Paint

What exactly are you looking at when you pick up a tube of oil paint?

Various brands of oil paint, including Gamblin, M Graham and Co., Winsor & Newton, Williamsburg Handmade Oil Colors, Michael Harding, and Rembrandt

Brand and Color Names:

Each manufacturer assigns color names based on tradition, marketing, or aesthetic appeal and they are not necessarily consistent across brands. For example, Naples Yellow from one brand might differ significantly from the same name by another manufacturer. It’s important to familiarize yourself with the naming conventions of your favorite paint brands but never rely solely on a color name when choosing a paint.

Series Number:

Most professional-grade paint brands assign a series number to each color, indicating its price category. The higher the series, the more expensive—often reflecting the rarity or cost of the pigment used. This doesn’t necessarily correlate to quality but can help you anticipate pricing within a range.

Pigment codes:

Perhaps the most important part of any paint tube is the pigment code: a standardized designation like PB29 (Pigment Blue 29, Ultramarine Blue) or PR101 (Pigment Red 101, Venetian Red). This code describes what pigment is inside the tube, regardless of the name on the front.

Back of paint tube showing the characteristics, including pigment code

Single-Pigment Paints vs. Mixtures:

A single-pigment paint contains only one pigment, while a mixture combines two or more. Single-pigment paints offer greater clarity, cleaner mixing potential, and more reliable archival qualities. Mixtures can be convenient but may behave unpredictably when mixed or age unevenly if they combine pigments with different lightfastness ratings.

Key Paint Characteristics to Understand

Lightfastness refers to a pigment’s resistance to fading when exposed to light. Most professional paints include a lightfastness rating on the tube, either based on ASTM standards (with categories like I = Excellent and II = Very Good) or proprietary scales from individual manufacturers. The higher the lightfastness of your pigments, the better your work will hold up to long-term display.

Pigments naturally fall along a spectrum from opaque to transparent, affecting how they cover previous layers or interact in glazes. Transparent colors are perfect for glazing and producing luminous effects, while opaque colors produce solid highlights and build well on thinner layers. Labels often indicate this characteristic through symbols or visual swatches on the tube.

The term “tinting strength” refers to how strongly a color influences a mixture. High tinting strength pigments like Phthalo Blue or Quinacridone Magenta can easily overpower a mixture, while colors like Yellow Ochre offer softer, more subtle shifts. Understanding relative tinting strength can prevent over-mixing and muddy colors.

Different pigments dry at different rates. Earth colors like Burnt Umber dry quickly, while colors like Alizarin Crimson or Titanium White dry more slowly. Understanding this helps you plan multi-layer work according to the fat-over-lean principle — applying slower-drying, more flexible layers over faster-drying ones to avoid cracking.

Various oil paints on a palette

Chemical Derivatives and Paint Bases

Historically, artists used earth pigments (like Yellow Ochre), mineral pigments (like Cobalt Blue), and later, modern synthetics (like Phthalo Green). Natural pigments like these often produce gentle, muted colors with excellent stability. In contrast, synthetic pigments tend to offer greater vibrancy, tinting strength, and in many cases, superior lightfastness. Neither is inherently superior, however, and both types should have their place on an artist’s palette

All paints are fundamentally just different particles suspended in various oils, the type of which affects drying time, color saturation, and long-term yellowing:

            •           Linseed oil: Traditional, strong film, yellows slightly over time.

            •           Walnut oil: Slower drying, minimal yellowing.

            •           Poppyseed oil: Slow drying, ideal for light colors, can be less durable.

            •           Safflower oil: Slow drying, resists yellowing, often used in whites and blues.

Manufacturers may also include stabilizers, driers, or extenders to adjust paint texture, drying time, or cost. Higher-end paints typically avoid unnecessary fillers, resulting in denser, more pigment-rich color.

Back of paint tube showing pigment color code, type of oil, and other characteristics

Understanding these characteristics isn’t purely an academic pursuit — it directly affects your creative decisions. Transparent pigments, for example, are excellent for glazing delicate skin tones or initial layering while opaque paints are superior for bold highlights or final layers.

The best way to start is by examining the labels on your current paint tubes. Compare pigment codes, lightfastness ratings, and opacity indicators. You might be surprised at what you find.

For deeper study, consider resources like The Artist’s Handbook of Materials and Techniques by Ralph Mayer, the ASTM standards for artists’ materials, or pigment guides provided by trusted paint manufacturers.

The more fluent you become in the language of paint characteristics, the more control you’ll have in your studio practice. Understanding the anatomy of a paint tube helps you mix color more effectively, build lasting work, and explore new techniques with confidence.

Recommended accompanying images:

●     Various paint tubes for visual walk diagram of how to read paint tube

●     Various pigments on neutral-toned palette (earth vs synthetic pigments and to show the effects of various binding agents)