Vegetable or Mineral
I have had the opportunity to study a wide variety of prehistoric painted artifacts from the NW Coast and have only found one object that had a color on it that wasn’t a natural pigment. I was fortunate in picking a time to do some research at University of British Columbia’s (UBC) Museum of Anthropology when they had several old Coast Salish horn rattles on loan from another museum. One of those rattles dated at 3-400 years old and was extraordinary in a number of ways, not the least of which were two small spots of pinkish red are on the backside. Both spots are very obviously berry juice rather than a pigment and are quite faded. After looking at hundreds, if not thousands, of artifacts, and finding only one that has vegetable color on it makes it quite apparent to me that NW Coast indigenous peoples clearly grasped the difference between a pigment and a dye.
Around the world throughout history many people have substituted vegetable matter for pigments with little success. Vegetable matter such as berries, flowers, leaves, roots, even bark are chemically and physically different from pigments, and while many work beautifully as dyes, they cannot give the same results as pigments. Dyes are colorants with small particulates which are soluble in water and typically need a mordant, or fixative, to make them bond semi permanently or permanently with the fibers of fabric. On leather, wood and other materials with which they can’t be fixed or bonded, they tend to fade rapidly, simply soak into the medium and can’t be seen, and are not water proof.
Pigments are pure colored powder of which the particles are not soluble in water, oils or resins. The colored particles are mixed with a liquid binder or vehicle (in the case of NW Coast native paints they were most often mixed with the lipids and proteins from salmon eggs very much like egg tempera used on ancient Mediterranean frescoes. Salmon egg paint displays much the same durability as egg tempera paint.) in which the particle is suspended. If there aren’t enough particulates in the binder you end up with a transparent, weakly colored paint. Mixing plenty of pigment into the binder gives an even textured and evenly opaque (opaque means not allowing any light or background show through) paint with good saturation of color. Most pigments, unlike vegetable dyes, are lightfast, waterproof and “stand” on the surface of the support (support is the material on which the paint is applied.)
The process someone had to go through to achieve a good paint was not simple even if one already knew where to find the pigment and knew the process. One has to go to the nearest deposit (which could be a long distance) and collect the pigment (pigment isn’t usually found just laying around on the ground here in the Northwest. You have to know from geologic indicators where it’s likely to be, then dig for it.) then clean it of debris and impurities. If it’s in a hard state (clay or stone) it needs to be broken down and ground to small grains. It can be cleaned of impurities such as silica and quartz by washing in a container and letting anything lighter in weight float off, or anything heavy sink to the bottom and then pouring off the lighter pigment into another container. It is then left in suspension, letting most of the fluid evaporate. When the pigment reaches a point where the water has evaporated but is still moist it can be ground into a paste (which is called levigating) at which time it’s easy to separate the smaller from larger particles. Often, at this stage the pigment is formed into a cake or ball and let dry for easy storage. The pigment can also be left until dry. Before mixing as paint it would need to be ground to a fine powder.
Grinding requires a fairly flat or hollowed surface without bumps or holes (although a smooth, polished surface won’t abrade the pigment grains and reduce them) and a pestle which fits comfortably in your hand and is flat or slightly convex on the bottom. In my research I’ve come across a number of grinding stones, all about 2-3 inches thick, of a fairly uniform shape, a bit smaller than a dinner plate and all have been hollowed at least minimally. Most of the grinding stones I’ve seen are made of fine grained sandstone and pestles are usually made of basalt.
When looking at pigment grinding stones, I’m always impressed by the work that went into the grinding stone alone. Fig 20. is a particularly good example of a mortar that was chosen wisely. Its shape is ergonomic, with the point on the left acting as a handle; I tested it and it can be gripped very comfortably in your hand while working. It is heavy enough to stay in place while working but light enough to carry around easily. But the time spent hollowing it is incalculable as with the small mortar below and with all the grinders, mortars and dishes I’ve studied. I’ve seen many small mortars like this which fit into the palm of a hand perfectly. While the outer shape may be mostly natural, the hollow is obviously human work. The uniformity of the walls of the small mortar in Fig 22. along with the little rolled lip makes this mortar a piece of artwork unto itself.
Studying pigment grinders, mortars, paint bowls and brushes has shown me very clearly that early artists were quite meticulous in the use of their tools. Grinding stones, mortars, paint bowls and brushes all indicate the use of a single pigment for each; to date I have yet to see any of these tools with more than one pigment on it. This means that any artist would have to have each of those tools for each color used. This coincides with my own practices and care of my tools. Early in my career as an artist I learned to have separate tools for each pigment and paint I use. I discovered that red paint (I use Golden Acrylics exclusively when working with manufactured paint) wears out my brushes (I use only one brand and size of brush for all my work) faster than any other color no matter what I’m painting on: wood, leather, cedar bark, grandsons, etc. And I learned quickly that it’s all but impossible to clean all the paint out of a brush before using it for another color. I use separate containers of water for rinsing my brushes of each color. Since I only have one large mortar for breaking down the chunkier pieces of pigment, I scour it thoroughly and bleach it so as not to contaminate the next pigment I grind in it. I have small mortars and pestles for grinding different colors finely. The fact that artists were meticulous in using individual tools for each color is yet another aspect to the lengthy task of getting to the point where they could actually apply paint. An artist would have to make a number of mortars, grinding stones, etc., as part of the prep work. Fortunately, once made, if taken care of they could be used for lifetimes if not generations.
Once ground the pigment can be stored for indefinite periods of time. When the artist is ready to use it, he would have finely ground some in a mortar; typically only enough for one day would be mixed with the binder because the paint would dry out and be unusable by the next day. He’d (I say “he” because there is no evidence of women carvers and painters until modern times) then add salmon egg oil and human spit to the pigment to create paint. (While many other binders were available: blood, hide glue, bird eggs…the almost exclusive use of salmon eggs leads me to believe there was some potent relevance for using salmon eggs.) To get the salmon egg oil, fresh skeins of eggs were mashed and broken open in a container and let sit until the membranes separated from the fats and proteins inside the eggs. The membranes were then skimmed off and a “soup” was ready for use as a pigment binder. If fresh eggs weren’t available, dried eggs were chewed and the resulting mash was spit into a container and mixed with the pigment; it’s easy enough to just push the dried membranes out of your way when painting. Early people became aware that paint which was mixed with human spit adheres better and spit became part of all the paint recipes (some of the earliest cave paintings are handprints which have been made by putting pigment in the mouth and spitting it around the hand). Human spit carries an enzyme which helps to bind the pigment molecules together. Sometimes pigments were simply mixed with water and spit then painted on. With this technique I’ve discovered that adding some spit helps to keep the pigment evenly dispersed in the water and helps with adhesion.
Altering hue and patina
In my research I’ve had the opportunity to study many artifacts, some of which are painted with salmon-egg paint, some of which are painted with water-based paint. I have found that there is little difference in the durability between the two techniques, both showing good adhesion and about equal signs of wear through use. What does occur is a change in texture, patina and hue. When pigments are mixed with water they have a gouache-like texture and powdery patina; the hue remains the same as the pigment. When mixed with salmon egg oils the paint takes on an almost plastic texture and a satiny finish. The hue is usually darkened with a little more saturation of color. Of course, this also depends upon how much pigment has been mixed into the binder. When the pigment has been heavily loaded it overrides the oils and can take on a flat, grainy finish. The oils in salmon eggs aren’t the only fat that changes the paint though. Fig 23. is a detail of a spoked spindle whorl painted with red ochre and celadonite (green mineral pigment) paint. The surface paint of this spindle whorl has a smooth satiny finish and both pigments have darkened from the lanolin soaking into it from spinning sheep wool.
In Fig 24. you can see along the edge of one spoke where the original green pigment is a pale, soft color with a flat finish. This is what the green originally looked like all over. This is just one example of artifacts I’ve studied that show alterations like this. Many objects that were often held show by the altered paint where they’ve been touched most and picked up oils from hands; sometimes there are actually fingerprints left on a piece. There seems to be little difference in the durability of water-based and oil-based paints.
Even today it’s an extremely time-consuming and detailed process to make paint. For colors of which I don’t have large amounts of natural pigment, I can buy them from reliable suppliers. I don’t like doing this though. If I’m working on a piece that has some natural pigments on it, I won’t shift to using purchased pigments. Although it is a lengthy process to do it today, I’m lucky in that I have plenty of light, warmth, premade mortars and brushes, reusable containers for water, a cushy chair and workbench, and containers that seal tightly for storing paint so I don’t have to make a new batch each day. I try to imagine how difficult it must have been to do this under the rough conditions that artists lived in and just can’t imagine myself pulling it off. It takes determination, stamina, knowledge, technical skills and physical abilities, and a deep commitment to achieve just one dish of paint.