Professor Kehlet demonstrating how to mix pigment with binders like linseed oil, egg yolk, and guar gum.
The Textile Dye Garden Vol. 1 Swatch Book on display with several of our lake pigments.
Swatches of paint demonstrating the varying colors that can be achieved through different binders.
The first step in making lake pigments is to make a dye concentrate. This can be done either by simmering plant matter in water for 1-3 hours, or by using a previously used dye bath. (Note that dye baths which have already been partially exhausted will produce weaker colors of lake pigment).
(Marigold and Red/Purple Dahlia concentrates)
The above shows a highly concentrated Marigold dye bath that bubbled over the jar when soda ash was added.
Test the dye bath with pH strips and adjust your mixture until the pH strip reads neutral (pH of 7). If the mixture is basic, add more soda ash. If it is acidic, add more alum. Neutralizing the solution allows the pigment from the bath to settle on the bottom of the container while the supernatant (the clear liquid that does not contain pigment) sits on top. It can take 24-48 hours for all of the pigment to settle to the bottom. This process is called precipitation.
Pigments settled and ready for straining.
Once settled, line a second container with a coffee filter. Pour off the majority of the supernatant into the sink, and then slowly pour the rest of the sedimented liquid through the coffee filter until you are left with a gelatinous substance. When the liquid has fully strained through, the pigment left behind must be washed to remove excess minerals. This is done by scraping the pigmented goo off the coffee filter into a jar and adding 2mm of water above the substance into the jar. Let this sit overnight and then repeat the straining process with a new coffee filter.
Gelatinus substance from Madder being strained through the filter
Allow the sediment to completely dry in the coffee filters. This can take several days.
Once dry, crush the pigments into a fine powder using a mortar and pestle. The pigment is now ready to be mixed with binders for paint, such as guar gum, egg yolk, or oil.
On a smooth surface like plastic or glass, use a palette knife or brush to combine the pigment with the binder.