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Category: buying paints

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The devil’s in the details

Pam’s paints weren’t cheap; they were by reputable manufacturers. But she was caught in the maze of historic names and convenience mixes.

Spring Allee, 14X18, oil on archival canvasboard, available.

Last week my students did a green-mixing exercise. Pam Otis had a tough time getting the proper mixes out of the yellows on her palette. After class, she sent me photos of every yellow she had. I spent an instructive half-hour happily looking up each tube.

I know, generally, what’s in colors, but different manufacturers have different ways of getting to that point. If the paint tube isn’t marked (or has been crimped or damaged so you can’t read the tiny type), you must research the paint on the manufacturer’s site. Often, you’ll learn something, because paints are constantly changing.

Vineyard, 30X40, oil on canvas, available.

Some changes are due to market conditions. PO49, quinacridone gold, was a very useful color (as all the quinacridones are). However, it was discontinued by the auto industry in 2001. The fine arts market for pigments is miniscule, so PO49 disappeared. Most modern quinacridone golds are convenience mixes of quinacridone orange (PO48) and nickel azo yellow (PY150). Both are perfectly fine pigments, but they work differently in mixes than the original pigment.

Other substitutions are more inscrutable. The siennas are ancient pigments made of dirt—a mixture of iron and manganese oxides, to be specific. In its natural state, this pigment is yellow-brown and called raw sienna. Cooked, it turns red and is burnt sienna. Along with ochre and umber, raw sienna was among the first pigments ever used by prehistoric humans. It has been used ever since, because it’s cheap, plentiful, harmless, and doesn’t fade. Modern earth pigments are all manufactured analogues, but are chemically indistinguishable from the old mined ore.

I have no idea why Winsor & Newton substitutes a combination of burnt sienna (PR101) and yellow ochre (PY42) for ordinary raw sienna. But that may be why some yellow ochres and raw siennas are indistinguishable out of the tube.

Bracken fern, 9X12, oil on archival canvasboard, available.

A hue is a blend of less-expensive pigments. There is nothing inherently wrong with hues, but they don’t behave the same as the pigments they’re named after. “Cadmium yellow hue” may look like cadmium yellow coming out of the tube, but it makes insipid greens.

Then there is the stuff that watercolorists call Gamboge. The real thing came from tapping the latex of the Garcinia, or Gamboge Tree. It’s a beautiful, transparent, non-staining orange-yellow, but it’s also extremely fugitive (as vegetable dyes tend to be). So, manufacturers substitute other pigments and call the result New Gamboge. The most common ingredients are nickel azo yellow and anthrapyrimidine yellow (PY108) However, there are as many formulas as there are manufacturers, and every combination behaves differently.

Spring Greens, 8X10, oil on archival canvasboard, available.

The origins of Indian yellow have long been disputed. It was said that it was extracted from the urine of cows fed a diet of only mango leaves. 20th century, art historians doubted this, but recent chemical analysis of historic samples confirm the source as animal urine.

We now reject the idea of starving cows to create pretty pigments (although euxanthic acid can be synthesized in the lab). Today we use combinations of nickel azo, hansa yellow, and quinacridone burnt orange. It’s a terrific paint for making dark greens. The trouble, again, is that every manufacturer has its own formula for Indian Yellow.

Pam’s paints weren’t cheap; they were by reputable manufacturers. But she was caught in the maze of historic names and convenience mixes. Knowing how to read the CII code on your paint tube is important.

The CII code consists of two letters and some numbers. Most paints start with a “P” which means it’s a pigment, not a dye. The next letter is the color family:  PR is red, PY is yellow, etc. The number is the specific pigment included in the tube.

Save this link somewhere accessible from your phone. You’ll need it when you shop. This pigment guide was built for watercolors but is generally true across all media. 

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The problem with supply lists

I should KonMari my paint collection, not add to it. We go to workshops weighed down with too much stuff.

No, I don’t need any more watercolor pigments.
Many years ago, I took a workshop from a figure painter who specified cadmium green. I came home with an unopened tube and dropped it in a drawer. It’s still unopened.
I have great sympathy for students faced with a new supply list. In some instances, buying from them is redundant. For example, my list calls for Prussian blue, but if you already have phthalo blue, you’ve already got an excellent pigment for that color space.
It helps to understand the instructor’s reasoning. My list is based on paired primaries because I believe it allows the greatest range in color space. It occasionally changes as my painting technique evolves.  
Students usually show up with too much stuff because they don’t want to be caught without something they need. Most of what they carry, they never use. I’m feeling that urge to over-pack as I assemble the materials for Poppy Balser’s workshop in May.  Poppy, like me, is loath to send her students on spending sprees. However, it makes no sense to drive that distance and not be prepared.
And I don’t need a new mixing tray, either.
I trotted out my watercolor basket expecting to have to fill in color gaps. Actually, I should KonMarimy paints. What’s in the picture, above, is probably a quarter of the tubes in my basket. Does anyone really need five tubes of ‘opera pink’? More importantly, what is ‘opera pink,’ anyway?
Manufacturers love labeling convenience mixes with historic names. Consider Naples Yellow, used from the 18th to the 20th century. The real pigment is toxic lead antimonate. Modern paints labeled “Naples yellow” are made with a mix of modern pigments. You can make your own easily enough with white and yellow ochre.
That is the only name that really matters.
Pigments are listed on the tubes of all major paint makers in the form of Colour Index (CI) numbers. These are in tiny lettering on the side of most paint tubes. If the first letter is a “P,” that’s a pigment; if it’s an “N,” that’s a lake of a naturally-occurring substance like cochineal. The second letter tells you the general color family. The third tells you the actual pigment used.
A glance at my tube of ‘opera pink’ tells me it’s really PR122+BV10. The first is my old friend quinacridone magenta. Unfortunately, the second is a dye, rhodamine B, which bleeds and isn’t lightfast at all. I should pitch all five of those tubes.
My brushes, on the other hand, need help. New Yorkers will recognize some as being from the cheap bin at Pearl Paint.
If there is more than one CI number on the tube, you’re actually buying a hue or convenience mix. Many paint manufacturers sell hues of expensive pigments like the cadmiums and cerulean blue. They’re not consistent across brands, and they never have the handling characteristics of the more expensive paints they’re meant to imitate.
As with opera pink, even if the main pigment is lightfast, its partner may not be. Almost always, using single-pigment paint gives you the most flexibility in mixing.
There are many pigment guides on the web. Here is my favorite. Although it’s meant for watercolor, pigments are consistent across all media.