This is not a review or endorsement of any online art supplier; I think all of the well known ones are probably fine, and each has their plusses and minuses.

This is about a resource that a particular art supplier, Dick Blick, offers as part of their online catalog. When browsing for paints — whether oil, acrylic, watercolor, gouache, pastels or other — the Blick site offers the ability to drill down into information about the pigments used in various paint colors.

The pigments in some paints are fairly straightforward. When you buy a tube of Chromium Oxide Green, you can reasonably expect the primary pigment to be oxide of chromium. The metal cadmium (cadmium sulfide or cadmium-zinc sulfide) is likewise the expected pigment in Cadmium Yellow.

The constitution of other paint colors is often less clear. True Naples Yellow, for example, was classically made with lead, and only a few select paint makers offer a genuine Naples Yellow (an example would be Vasari Colors). Most paint manufacturers feel at liberty to call a paint “Naples Yellow” that is made with any number of other more contemporary pigments.

By the same token, a color like “Paynes Grey”, though it has historic formulas, is a blend open to a variety of modern interpretations. So-called “Permanent Alizarin Crimson” is never actually that, but a formulation of other colors (that should more properly be called “Alizarin Crimson Hue”), the recipe for which is different from brand to brand.

So those like myself who are often curious about the constitution of various paint colors are left to wonder about what pigments are in a given paint. Sometimes the manufacturers will give that information on their websites, but it’s scattered and inconsistent.

This is where I find the resources for individual paint colors on the Blick website useful.

When you browse the Blick website for any given paint type and manufacturer — for example, Winsor and Newton Watercolors — you’re presented with a list of small color swatches and names. What’s not made obvious is that the item number in the left column (though oddly, not the paint name itself) is linked to a detail page for that particular paint color.

This is further divided by tabs into a general description with a small photographic paint swatch, a “Color Swatch” tab with a larger swatch — usually with tints or dilutions of the paint, and a “Pigment Info” tab.

In the latter, Blick has provided a list of the pigments used to make up that particular color, as well as a descriptive background on those pigments, their chemical composition, transparency, lightfastness, toxicity, history and alternate nomenclature.

Caveat: I have to assume that Blick has collected this information from the manufacturers, but I have no way to determine how accurate or consistent it may be. I offer it as something interesting and possibly useful for those who are interested to know what’s in a given paint.

Also, this only includes information on those manufacturers who deal with the large art materials suppliers, and doesn’t include independents like Vasari Colors, Robert Doak, RGH and Blue Ridge Oil Paints, but it can give you a general picture of the variety of pigments in given colors.

In the images above, I’ve used some well-known manufacturers of watercolor to provide an illustration of the variety of pigments in their formulations for the same color name.