Lake Pigments

As part of Pratt's Earth Action Week events, the Textile Dye Garden hosted a paint-making workshop using lake pigments made from our 2021 dried yield. At our event, Textile Dye Garden team member Lyric Caramto demonstrated the process of making lake pigments, and Math and Science Professor Cindie Kehlet demonstrated how to use those pigments to make egg tempera, watercolor, and oil paint. Lake pigments are an ecologically mindful way to make paints to use on paper or canvas. Below, Lyric Caramto and Mina Afkhami walk us through the process of making the pigments.

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.

Lyric Caramto and Mina Afkhami are both in the '22 graduating class majoring in Fashion design and double minoring in Sustainability and Textile Design, as well as being team members of the Textile Dye Garden. The two of them created several lake pigments and walk us through the process and discuss their experience.

How do natural dyes play into your artistic practice at Pratt?

Caramto: In my artistic practice I enjoy the unpredictable color palettes that can be achieved with natural dyes, especially when using color modifiers such as iron or soda ash on naturally dyed fabrics. 

Afkhami: I learned about natural dying techniques my second semester at Pratt, and immediately connected with a variety of techniques that I have now made my own. I have been incorporating natural dyes into my artist practice, both within and outside of school ever since then, and even dyed 95% of the fabrics I used in my thesis collection. 

Where did you learn about Lake Pigments from?

Caramto: I learned about lake pigments from video resources online. A video I found particularly helpful was by “The Barefoot Dyer”.

Afkhami: I briefly learned about lake pigments in one of my painting classes in the beginning of my academic career at Pratt, but we didn’t learn in depth about the process for making them. I learned about the process and technicalities of making lake pigments in preparation for the Textile Dye Garden workshop. 

Given your backgrounds in fashion, what was it like to make pigments for paint and use natural dyes in a new way?

Caramto: It was super interesting to experience every step of the process. Every dye bath reacted to the chemicals differently, with some mixtures foaming drastically and others taking longer to dry out. In the end we ended up with a wide range of vibrant colors. 

Afkhami: I am always interested in discovering new ways to use the color from organic materials in my artwork. I love that making lake pigments allows you to give another life to dye baths that you might have otherwise disposed of, especially if they are close to being exhausted. The artist process becomes more of a closed loop cycle, and therefore is more sustainable. I always aim for my own practices to be as low impact to the environment as possible, and this is another great way to do so, especially as someone who uses natural dyes so often. This project was particularly special because it was a continuation of using the plants we cultivated in the garden during the 2021 growing season, so we have known where these materials have been throughout their entire lifespan, and there was little to no waste at the end of the process. As far as the creation of the pigments, I was incredibly fascinated by the entire process, from mixing the chemicals to invoke the precipitation process to grinding them with the mortar and pestle. It was very exciting to come back after a day or two and watch the way the materials changed from liquid to solid, and even more exciting to paint with the pigments.

Has the process of making Lake Pigments inspired you to explore anything new with natural dyes?

Caramto: Gina Gregorio (Textile Dye Garden faculty lead) suggested that we look into how to make crayons out of the pigments, which I would love to use in tandem with the paints we made. 

Afkhami: I am very interested in the way that this process can become a sustainable, closed-loop cycle. In theory, the supernatant water could be used to water the next growing season’s plants, or for other projects and dye baths, limiting resource use even further. This process has inspired me to explore even more unconventional ways to use the plant matter we grow for other artistic mediums that go outside of my textile and fashion specialty. 

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.

Next, add aluminum potassium sulfate and soda ash. Measure the dye concentrate to determine quantities for each. Add 5 grams of alum to the dye bath for every 100 ml of liquid. Halve the quantity of alum to determine the soda ash quantity. (2.5g of soda ash per 5g of alum). Pre-dissolve the alum in a container with water and add to the dye bath, stirring to combine. Next, stir in the soda ash. Assure you have lots of room in your container with the dye bath, as the soda ash will cause the solution to foam.

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. 

Dye concentrates

Precipitation process

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

Straining process

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.