Pigments
by John Marshall
Pigments may be minerals, such as various rusts and dirts, or they may be vegetable, such as flower pollen or many lakes. All pigments will need to be adhered to the fabric with a binder. I prefer soymilk.
Minerals are ground to a fine powder in a mortar and pestle, mixed with the soy and applied much like a paint. Vegetable pigments may be finely ground plant parts, as in the case of pollen, or they may be color that has been leached from the plant in a more pure form, as in lakes. Pigments are available commercially or you may make your own.
▶︎One of the easiest ways to make pigments is simply to pour whatever dye you have left over from a given project into a glass pan and allow the contents to dry. The dish should be shallow enough to allow the dye to dry before it begins to deteriorate. Once dry, simply scrape it up and store it away for later. You may want to allow several layers to dry, one on top of the other, until a sufficiently thick layer has formed to warrant taking time to scrape it. Do not save dyes that have been mixed with soy milk. If they don't sour first, the protein will harden the pigment and keep it from working well the second time around.
▶︎Mineral pigments are fairly easy to prepare on your own. Find a local source for interesting colors of dirt. In the Central Valley of California, we have very rich topsoil. Just below that layer is a compacted clay called hard pan. Below the clay is a beautiful yellow soil – terrible for growing crops, but ideal for pigments. Simply wash the soil until it is free of rocks and debris, separate out the smallest particles for use, and you have a wonderful pigment ideally suited to our purposes.
▶︎Pigments may also be prepared as lakes. A lake is a pigment that has been flocculated (separated) out of a juice dye. Basically, you take a juice dye and add any hydroxide (calcium-hydroxide, etc.) until the pigment separates out. This is how carmine lake, a popular color in watercolors, is manufactured. Shown are the basic steps that go into making a lake from the insect cocheneal.
▶︎There are many natural sources for bonding agents that may be used with pigments. I prefer soymilk because it is easy to prepare, cheap, and more importantly, leaves you with the best hand. As the soymilk dries and starts to cure, it absorbs oxygen from the air, helping the protein to form a very strong bonding agent that can't easily be dissolved in water.
▶︎If you are not particularly interested in making your own pigments, consider using high quality watercolors as a substitute.
