The Stuff of Paint

Watercolor: What it is.

Gum Arabic Crystals Traditional transparent watercolor is finely ground pigment in a water-soluble binder such as gum arabic. Gum arabic is water-soluble gum produced by a species of the acacia tree and is available in crystalline form or in prepared solutions. The gum arabic crystals or granules are transparent when pure, but less highly refined varieties can be yellowish to honey colored. Gum arabic is also used in inks, adhesives, pharmaceuticals, and confections (it’s non-toxic and tasteless).

Other binders used for watercolor paint have included Tragacanth, a gum optained from various asian shrubs, and fish glue. Glycerine, dextrin, crystallized sugar, syrup, or honey can be added to modify the working texture of the paint, counteracting the brittle quality of the gum arabic a bit. Ox gall can be added as a surfecant or wetting agent to aid the free flow of washes. (Think dishwasher soap’s “sheeting action”) Oil of cloves can be added to deter the growth of molds which can happen on cheap quality paints.

Which water?

Distilled or boiled water are said to give the best results when painting, avoiding adulterants that may affect certain pigments. I use tap water.

On Student Grades and cheaper paints

Cheaper paints tend to have excess binder that can result in a glossy sheen in a finished wash of color. Student grade paints use less refined pigments mixed with a neutral filler pigment. Some manufacturers offer “hues” of a color such as “cobalt blue hue” or “manganese blue hue”. These are mixed using a less expensive pigments, Ultramarine Blue and Pthalocyanine Blue in this case, to simulate the more expensive genuine color. They are a cheaper way to go but their tinting strength is generally poor compared to the “real” pigments. You can learn to mix your own “hue” colors from a rather limited palette.