Natural pigments

I love this blog from colourlovers.com on prehistoric colors and natural pigments still in use today. The photo of the earth colors in their natural state is amazing. A student in one of my classes some years ago had collected these pigments in Italy and brought them to show us--incredibly beautiful.

Speaking of pigments, I finally got around to checking out four more M. Graham watercolors on my chart. All are richly pigmented and I liked them, except I didn't find the Manganese Blue Hue to be near enough to the original to merit the name. However, it's a beautiful color and would work well as a cyan in an expanded palette. The Cadmium Yellow Deep is rich and opaque, and I love the Permanent Green Pale. I don't care much for the phthalocyanine greens in the yellow shades, but this one is a different mixture. Clear and bright. The M. Graham Terra Rosa is opaque, like Indian Red in other brands. I like this color for Southwestern themes. My chart is complete, except for Mineral Violet. One of these days I'll run across it, I'm sure. If I have it, it is buried somewhere in the vicinity of my drafting table. Know what I mean?

M. Graham paints

I swore I'd never do another paint comparison, but when M. Graham of Oregon came out with more than 20 new colors, I couldn't resist. The image shows my original chart on the left and the new colors on the right. While it isn't easy to distinguish the colors in the image, you can see how brilliant they are. I tested for transparency, tinting strength, reaction to salt*, and staining characteristic. I find most of the Graham pigments saturated and of a pleasing consistency. I especially like the reds in the original line, and now they have added Scarlet Pyrrol (PO 73), luscious Pyrrol Red (PR 254), Permanent Alizarin Crimson (PR 264), Maroon Perylene (PR 179)and bright Azo Orange (PO 62). Hansa Yellow (PY3) and Hansa Yellow Deep (PY97) fill the bill for cool and warm semi-transparent yellows. I also like Anthraquinone Blue (PB60), which resembles Indanthrone Blues from other manufacturers. Cobalt Teal (PB28), a light turquoise, appeals to me, while Turquoise (PB15:3+PG7) could be a little greener to suit my taste. A new range of synthetic earth pigments from yellows to reds has a lot of possibilities for low-intensity palettes. The Nickel Quinacridone Gold (PO48+PY150) lacks the glow of the Quin Gold pigment (no longer available), but is a lovely color on its own. Indian Yellow (PY110) is too orange in my opinion. Colors with less powerful tinting strength, like Ultramarine Pink (PR258), Cobalt Green (PG50), Cobalt Violet (PV14) and Ultramarine Violet Deep (PV15) work well on a delicate palette, but might be easily overpowered by many of the colors in the line. The Cerulean Blue Deep (PB36) looks more like a weak phthalo blue and doesn't appear to granulate as I would expect a cerulean blue to do.

On the whole, I like M. Graham colors very much. One of the ingredients is honey, a traditional method of watercolor manufacturing. The consistency of the paint is very nice--creamy and easily soluble in water. Some colors may seem a little stickier than others, but this may be the nature of the pigment. The new colors give a much needed boost to the available range in watercolors. M. Graham watercolors are more reasonably priced than many imported brands and give good value for the price. I have favorite colors among many different brands. For more information on this paint, see handprint.com.

*I don't recommend using salt for fine-art watercolors, but the effect can be used for illustration, note cards and crafts, in which case it's important to know which pigments will react to salt in a damp wash.

More about Color Index Names

I'm not sure when ASTM assigned numbers to pigments, but it has been some time ago. Originally they did their testing for automotive and commercial paints. When they turned to artists' colors, I think it sort of whacked artists over the head. It was a shock to discover that so many of their favorite colors were fugitive or had fugitive pigments in their mixtures. ASTM set a voluntary standard for paints and paint labeling and quite a few manufacturers have complied by listing this information on their paint labels. Most are U.S. producers. The Color Index Names (which are actually letters and numbers, e.g., PR 254 means "pigment red, number 254," which is pyrrol red)are useful, but brands may look different, even with the same pigment. One of the more consistent colors is phthalocyanine blue green shade, PB 15:3, which has a different name in every brand of paint. It can be a challenge if you run out of paint and try to match a color, but you have a better chance if you know the ASTM name.

Pigment intensity in watercolor

For my watercolor class yesterday I demonstrated intensity, which is the difference between bright and dull colors. For some reason this is hard for a lot of artists to understand--that paint in a tube is high intensity or low intensity before it is mixed with another color. Several have used yellow ochre as the only yellow on their palettes and wonder why their paintings don't seem bright.

This chart shows what I did. I painted a swatch of yellow ochre at top-center. Then I made a swatch of gamboge to the far left leaving a space between them. The difference in intensity was obvious. Between the two I made a swatch of quinacridone gold, which they could see is brighter than ochre, but not as bright as gamboge. (Just below the gamboge is a cool lemon yellow, but I didn't emphasis the temperature difference, as that will be a later lesson.)

I continued the comparisons at the top-right with bright vermilion and low-intensity brown madder. In the lower left corner I painted indigo at left, phthalocyanine blue red shade to the right of indigo and indanthrone Blue just above. Again, the differences in intensity are obvious. But this was a revelation to many students, who hadn't previously observed this in their paints.

The mingling at the lower right shows how I test color schemes to see if I like the combinations, which I do when I begin a painting. I drop a little of each color onto damp paper, then push them around a bit to see what mixtures they make. This combination uses the low-intensity colors: brown madder, yellow ochre and indigo. I dropped in a tiny bit of vermilion to jazz up the brown madder. The low-intensity colors surrounding it make the color sing. This looks like an exciting combination for a painting.

Note: The colors on your monitor don't match the paints perfectly, so you need to do your own swatches. Also, brands may differ greatly in pigments having the same name.