The painter judges paint pigments according to two criteria: how they handle during the painting, and how they look when the painting is done. (Most painters are thoughtless about paint lightfastness and toxicity.)
The differences among pigments on these two criteria seem so large, and so apparently useful in producing different painting effects, that artists traditionally select pigments with similar or harmonizing attributes to form a single palette. This page categorizes watercolor pigments into different palette types, listed in the links at right.
The prevailing dogma about watercolors is represented by Jim Kosvanec's very fine color wheel book: some pigments are transparent, others are opaque, still others are staining and others are not, and you need to choose and mix pigments carefully to match these characteristics to best effect.
On one hand, this is essentially true: paints do differ in many attributes besides color. On the other hand, few watercolors are completely transparent, and whether they stain or not depends as much on the surface and sizing of the paper you use as it does on the paint itself. A lot depends on what you are trying to represent, how you are trying to represent it, and what are the characteristics of all the other paints put into the painting.
Style and technique trump almost every other consideration, and the qualities of materials are only desirable or objectionable in the context in which they are used.
For that reason I list pigments in multiple categories, rather than in only one. I also suggest other areas to focus your attention the importance of different papers or paint manufacturers in how much a pigment stains, and the usefulness of diluting opaque pigments to create greater transparency.
The major complication in the selection of a harmonious palette is that pigment behavior depends on the brand of paint, because each brand buys pigments of different quality and formulates paints with a different backbone composition. This point is often confused or ignored even in apparently knowledgeable art books.
In his often useful The Watercolorist's Essential Notebook, Gordon MacKenzie writes that indian yellow is a "staining, transparent color," and permanent rose is a "nonstaining, transparent color." These observations are worthless. The names MacKenzie has used are the paint marketing names, not the names of the pigments in the paints.
What is actually in a paint labeled "indian yellow" or "permanent rose," and how the paint behaves, can vary considerably depending on the brand of paint you are talking about and which pigment(s) that brand has decided to put into that paint. Thus, paints sold as "indian yellow" are made from at least five different pigments or pigment mixtures, depending on brand: diarylide yellow (PY83), anthrapyramidine yellow (PY108), isoindolinone yellow (PY139), nickel dioxine yellow (PY153) or benzimidazolone yellow (PY154). These paints range from transparent to semiopaque, and from nonstaining to heavily staining but only one of these paints (by Utrecht) was both transparent and nonstaining. Do you suppose that was the paint MacKenzie was talking about?
Even with a fairly unambiguous marketing name, such as "permanent rose" (which nowadays always means a magenta shade of quinacridone violet, PV19), or even when referring to pigments using the pigment color index name, the handling attributes of the paint can vary considerably depend on the pigment in the paint, due to differences in particle size, chemical purity, vehicle ingredients, manufacturing additives, and several other arcane factors. The quinacridone rose offered by the nine paint brands that I tested, all of them supposedly "the same" pigment, present significant differences in handling attributes from completely transparent to semiopaque, from moderately to heavily staining and they present equally large differences in hue, texture and lightfastness. Yet none of the "permanent rose" paints I tested came out as "nonstaining," as MacKenzie claims!
There are also broad differences in the brand style of different paint lines: Old Holland watercolors tend to be dull and gummy, and the gum makes them almost always lightly staining or completely nonstaining; M. Graham and Daniel Smith use a high pigment load which makes their colors darker and more staining; Daler-Rowney paints tend to be opaque while Utrecht paints are often the most transparent ... and so on.
General declarations about paint "colors" "permanent rose is a nonstaining, transparent color" may seem to offer conclusive guidance, but they don't, unless you specify which pigment and brand of paint you mean.
I've just argued that this page is not really worth reading ... but there is a long oral tradition among painters who like to categorize paints, and this page can serve as a brief guide or index to finding the pigments you want.
The pigment listings on this page are based on the average attributes of each pigment across several brands (when applicable). Please refer to the ratings and the notes for specific brands of paint or pigments in the guide to watercolor pigments.
Many watercolor painters make an obsession, a fetish, of "transparent" paints. Yet with few exceptions, all watercolor paints will appear transparent if they are sufficiently diluted, or applied as a foundation layer in a painting.
Some watercolorists claim that transparent watercolor pigments meet two specific criteria. First, that light passes completely through the pigment particles, is reflected by the paper, and passes through the paint layer a second time on its way to the viewer creating an effect "like light through a stained glass window." Second, that the paint remains transparent even when applied in many layered glazes. Some painters even go out of their way to build up glazed layers of paint in an attempt to emphasize this attribute.
The truth is that almost no modern watercolor pigment is transparent in the way watercolorists believe. For the gory details, see my discussion of the luminosity myth. The most transparent appearing pigments in use today the phthalocyanine blues and greens, hansa yellows, iron [prussian] blue, unadulterated quinacridones or ultramarine blue will create a visibly opaque discoloration if painted in several layers over a dark gray, waterproof ink or dried out on a black acrylic sheet. All other pigments have a refractive index greater than 1.5 meaning that they are more likely to scatter light at their surface, rather than transmit it like glass.
When paints are properly diluted and skillfully applied in single, juicy brushstrokes and without fussing over the paint as it is drying the practical difference between "transparent" and "opaque" paints is negligible. In glazes made with diluted opaque colors, the indvidual pigment particles act much like the individual benday dots in a halftone image: the pigment particles (dots) absorb or reflect light directly, but because they do not completely cover the paper surface, the paper also reflects light of its own. The visual mixture of the two produces a luminous color effect.
I rated paint transparency as the masstone hiding power of optimally diluted paint over solid black lines on white paper. The table shows the pigments rated most transparent around the 12 color points of the tertiary color wheel. (For background on the paints located at these color points, see the detailed notes to the visual color wheel.)
Unfortunately, many of the completely transparent pigments (rose madder, alizarin crimson, aureolin) are also impermanent, and the modern synthetic organic replacements are semitransparent to semiopaque. The repertory of paints used to achieve transparent effects has dwindled over time even as painting styles have evolved toward brighter colors and stronger value contrasts, which make atmospheric transparency less desirable anyway.
In the guide to watercolor pigments, I have been conservative in assessments of transparency, and in many cases the paints identified as "semitransparent" (transparency rating of 3) will work quite well in multiple glazes, especially when mixed with other semitransparent paints. Although they do not reach the transparency required in masstone, many of the earth pigments work well when applied in diluted washes or as foundation tints to semitransparent watercolors painted over them.
In contrast to the transparent paints, the paints listed here create a powdery or veiling texture over anything underneath them, at almost any concentration except a diluted tint.
In most cases, these paints have a relatively small pigment particle sizes or the pigment is unusually heavy in water, which means the pigment settles out of the paint solution relatively quickly and must be frequently stirred up with the brush while painting. Some artists refer to these as sedimentary paints as well as opaque.
The common association of "muddy colors" with opaque paints is reinforced by the fact that many opaque pigments are among the dull "earth" hues yellow, orange or red. Despite the negative associations with "sediment" or "mud" in transparent watercolors, these opaque paints contain some of the most beautiful pigments available. All the cadmiums and many of the "earth" pigments are among the most commonly chosen pigments in artists' palettes, which clearly refutes the notion that transparent pigments are required for transparent watercolor painting.
The key is in how much opaque colors are diluted, how thickly they are applied, whether they form the top or bottom layers of paint, and whether they contrast in hue or value with the colors used with them. Cadmium yellow will make a cloudy green if painted over a dark layer of phthalocyanine blue, but wonderfully glowing green if the phthalocyanine is painted on top.
The table shows the major opaque pigments around the 12 color points of the tertiary color wheel. (For background on the paints located at the tertiary color points, see the detailed notes to the visual color wheel.)
As with transparency, my evaluations of opacity are somewhat conservative: I only give a rating of 0 to paints that are really, really opaque (such as chromium oxide green or indian red). You may find some of the paints rated as opaque or semiopaque (ratings of 1 or 2) in the guide to watercolor pigments are still too dense for your purposes (most gouache paints get a 1 in the same rating system).
Some painters counsel against mixing opaque paints with strongly staining paints, such as the phthalocyanine blues and greens. It's a complete misconception that "staining" pigments can somehow dye or attach themselves to "opaque" pigments when mixed. I've found that "mud" is actually not a problem of paint mixing, but of how the colors are applied with the brush: "opaque" paints especially should be laid down and left alone. Fussing with them will dull only the color, and destroy the subtle granulated or flocculating textures produced by evaporating water.
I think opaque paints get a bum rap. You can get glorious watercolor effects by using them skillfully. As always, my suggestions are: think for yourself, experiment for yourself, and keep your eyes open to what pleases you.
The staining attributes of pigments are probably the most difficult to determine "objectively." The manufacturer of the pigment powder, the milling of the pigment, the vehicle formulation used by the paint manufacturer can all affect the staining power of a paint.
Worse, staining usually means the staining effects on watercolor paper, but variations in paper furnish, finish, weight and sizing also affect significantly how deeply a paint penetrates the paper and how difficult it is to remove through sponging or scraping.
Watercolor painters sometimes confuse "staining" with tinting strength or "mixing strength" but these are not the same thing. Staining is an effect on a surface, such as paper; tinting strength is an effect in a liquid, such as water. Both are usually increased as the pigment particle size gets smaller. But it is possible to reduce staining, without reducing tinting strength, by using a larger quantity of gum arabic, and a smaller amount of dispersant or humectant, in the paint's backbone formulation.
That said, nonstaining pigments tend to form a fairly consistent set, since a pigment that does not stain is rarely caused to stain by the paint formulation. (Iron oxide, cobalt and chrome pigments do vary in this way, however, because their staining power depends on the size of the pigment particles, which varies according to how the pigment was originally manufactured.)
As with transparent paints, the list of truly nonstaining pigments has dwindled over time: many of the original nonstaining colors were made from fugitive natural organic pigments. Nearly all modern synthetic organic pigments stain to some degree, because of their small particle size and manufacturing chemicals added to inhibit pigment clumping.
The table shows the major nonstaining pigments around the 12 color points of the tertiary color wheel. (For background on the paints located at the various color points, see the detailed notes to the visual color wheel.)
As with the other ratings, my evaluations of staining have been conservative, and you may find many paints listed as "lightly staining" (rating of 1) are more than acceptable for your purposes.
Anyone who has cleaned a plastic paint palette after using phthalocyanine blue or dioxazine violet knows that a handful of paints stain quite heavily and very little can be done with the paper furnish or sizing to change that fact.
These truly "staining" pigments are synthetic organics manufactured to submicron particle sizes that can actually adhere electrostatically to porous or nonporous substrates. The greater number of "staining" pigments are simply those with a very small particle size, which allows them to infiltrate tiny cavities or openings in the surfaces of paper, or plastics such as Yupo.
The comments in the previous section on the relativity of staining judgments apply also to the pigments listed here, since some manufacturers (Old Holland) strive to buffer or reduce the staining power of pigments, whereas others (M. Graham) do not.
Rather than try to distinguish between pigments that vary by manufacturer and those that don't, I suggest you use the guide to watercolor pigments to confirm any rating of "strongly staining" for the manufacturer you prefer to use.
The table shows the major staining pigments around the 12 color points of the tertiary color wheel. (For background on the paints located at these color points, see the detailed notes to the visual color wheel.)
Most of these strongly staining pigments are synthetic organic or inorganic pigments produced by manufacturing methods developed over the past few decades. It's probably fair to say that watercolor paints overall have become much more staining and less transparent in recent decades.
I think paper manufacturers have been laggard in responding to the evolution of watercolor paints. There is much that could be done to make watercolor papers more congenial to lifting paint layers, and to holding pigment on the surface, but this would require refinement in paper materials (both pulp and sizing) and different methods of manufacture.
Use the guide to watercolor papers to identify the sheets that respond best to lifting colors. Zerkall, for example, makes a wonderful watercolor paper that is in every respect up to the challenges offered by modern watercolor paints.
Compared to the saturation of watercolor pigments a century ago, modern watercolors offer some brilliant colors, all the better because they are also very lightfast.
The table only shows the most saturated pigments around the 12 color points of the tertiary color wheel. The value of the highest saturation varies by hue, and there are some high chroma pigments that receive a relatively lower saturation rating because of their dark (or light) value.
At each color point there may be other, similarly saturated pigments available; these alternatives are easy to identify on my artist's color wheel, and are described as "saturated" or "very saturated" in the guide to watercolor pigments.
The natural tendency of the beginner is to choose the brightest, most saturated colors possible. This becomes counterproductive once the painter learns how fundamental dull, unsaturated colors are to an effective painting; with a bright palette, the painter must spend a lot of time mixing the saturated colors with their complements (or with burnt sienna, a real band aid color when it comes to adjusting other paints) in order to dull them.
As a subdued complement to the saturated pigments, the "earth" palette consists of unsaturated, often sedimentary colors. Over time, this has become one of my favorite groups of pigments.
Earth colors can be as powerful as more saturated paintings, because they seem to glow with a magical, diaphanous light. Just remember to dilute them down, as some of these paints are quite muddy at full strength.
The earth colors are not popular in this age of gloss, acrylics and iridescence, but they have many positive attributes. They provide an effective painting framework for small touches of saturated color, which scintillate against the softer earth hues. Their mineral, slightly granular texture makes them easy to rewet and work with a brush to produce subtle gradations of tone almost like working pastels with a brush which makes them especially desirable in portrait flesh tones. They shift in value very little as they dry, making washes and mixtures easier to hit correctly on the first application. They remain effective colors even when diluted, whereas saturated colors can appear flimsy or flat as tints. Finally, they form more natural and varied color harmonies than more saturated colors, which can easily clash or jar through their brilliance.
I've been inclusive in preparing this list; many of the pigments listed are not true earth colors, but all the colors work well together and all have the attributes just described. I wanted to offer a large enough list to encourage your exploration of these paints. Select a handful of paints, such as the earth palette described in the guide to watercolor pigments, and try a painting for yourself. You may be pleasantly surprised at what you get.
The table shows the earth pigments around the 12 color points of the tertiary color wheel. (For background on the paints located at these color points, see the detailed notes to the visual color wheel.)
Remember that these pigments in general, but the warm earths in particular, are effective when strongly diluted. Although they are not exactly transparent colors, they become transparent when used as tints, and can produce some wonderfully evocative, atmospheric results.
See, for example, the paintings by Trevor Chamberlain to appreciate what can be done with this kind of palette.
Some pigments do not dry to the smooth finish we know from housepaints: they form subtle textures, caused by the size and shape of the pigment particles.
Textured pigments are relatively out of fashion today. In the effort to emulate the brilliance of acrylics or the precision of photography, textured pigments are often seen as undesirable.
I love these paints. To me an expressive resource unique to watercolors lies in the subtle textures of granulating paints left undisturbed to dry. Using them effectively requires skill and self control once you lay them down, you should let them dry without retouching! but I think they are well worth the effort.
The table shows the major flocculating or granulating pigments around the 12 color points of the tertiary color wheel.
It also lists some characteristically transparent or smooth pigments that can, if applied near full strength, produce a texturing effect that is caused by an unusually strong color contrast between different sized globules or clumps of paint. These are indicated by an asterisk (*).
For background on the paints located at these color points, see the detailed notes to the visual color wheel.
This list attempts to be comprehensive. There is a wide variety of texturing effects possible with watercolors; these pigments do not respond to wet-in-wet applications the same way. Pigment textures also vary considerably by manufacturer.
combining paints in a palette
So, after providing you with these tables of pigment attributes, it's worthwhile to consider how pigments should be combined in a palette.
The primary question is how consistently you paint in a single style, and what that style is. If you are a flashy modernist, then saturated paints are probably best for you; if you do a lot of lifting or sponging of color, then earth or texturing pigments are probably more interesting to you than staining pigments.
I don't share Kosvanec's specific prohibitions about combining pigments (for example, to avoid mixing a staining pigment with an opaque pigment). I agree that you may want to decide for yourself which pigments work well together but this always needs to be considered within a specific artistic style.
Creating broad prescriptions is only a way to narrow the opportunities of art.
And if you paint in different styles, or different types of paper, then the preferences you establish in one approach may not work in others. This means selecting "good all purpose paints" as the core of your palette, with a few added paints for special effects you love.
I've described the palettes of many working artists in the section on palette paintings. That may be a good place to start your search. Look for painting styles that intrigue you, study the palettes those artists use, and take those as a point of departure for your own explorations and experimentations.
Art is about your personal temperament. Choose what gives you pleasure.