Transform a noxious weed into vibrant yellow watercolor paint!
Safety:
Common Tansy is toxic if ingested and can irritate some people's skin upon contact. Wear gloves while working with Tansy, and as a precaution, work outdoors in a well-ventilated space. I have worked with many batches of Tansy with no issues, but caution is always advised.
Collecting Tansy:
Gather 1 sandwich-size ziplock bag of Tansy flower heads by cutting stems close to the base of the flower. The pigment is concentrated in the flowers, but a small amount of stem is fine.
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Extracting Pigment:
Add the Tansy flowers and stem remnants to a mesh bag* and secure with a rubber band. Add this to your dye pot** with enough water to cover the flowers; for me, this was about 1 liter. Heat on medium heat until steam is visible but not boiling. Lower the heat to prevent a boil and hold here for about 15 minutes. Turn off the heat and allow the flowers to sit in the hot water for another hour or longer.
*Alternatively, strain the dye bath before proceeding to the next step.
**Keep your dye pots and utensils separate from your personal cooking ware.
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Lake Pigments:
Making a lake pigment transforms water-soluble pigments into insoluble precipitates. This process allows you to make concentrated pigments that can be stored long-term and used in various products, such as watercolor paints, pastel sticks, and crayons.
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Pour the prepared dye extract liquid into a large jar. Do not exceed half the jar's volume, as the solution will expand during this process. Add 20 g of alum per liter of liquid. Dissolve the alum in hot water if your dye extract solution has already cooled. Next, dissolve 10 grams of calcium carbonate (per liter) in hot water and slowly pour it into the dye extract & alum mixture. Stir until well mixed.
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Allow the solution in the jar to settle for 24 hrs. The solution will begin to separate quickly, but waiting longer will allow more fine pigment to settle. At this point, you should have 2 distinct layers. Carefully pour off as much of the top solution as possible. Add fresh water to the remaining pigment sludge in the bottom of your jar and stir well. Allow to settle again. Pour off the top solution, and add more water. Repeat this process for a total of 3 rinses. The rinsing process takes some time but is worth the wait as it improves the quality of the final pigment by removing unwanted solutes.
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After the third rinse, pour off the top solution without disturbing the pigment sludge on the bottom. Line a funnel with 2 coffee filters and place over a jar. Pour the pigment sludge into the funnel and allow it to drain until no liquid is visible. Remove the filter and lay flat to dry.
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At this point, you can use your wet lake pigment extraction or allow it to fully dry and store it for later use. If using a dry pigment, you will want to grind it with a mortar and pestle before mulling. Always wear a mask and work in a well-ventilated space when grinding pigments. The small particles should not be inhaled.
Mulling Your Lake Pigment
Place your wet or dry powdered lake pigment onto the grinding tray. Add 8 mL (~1.5 tsp) of watercolor binder per 1 tsp dry pigment, or 2 tsp wet pigment. Gently mix with your pallet knife. Use your muller to mix in a gentle circular motion until a smooth pigment is formed. More watercolor binder or a small amount of water can be added if the consistency is too thick. Periodically test your paint and continue mulling until the desired smoothness is achieved. Use your pallet knife to transfer the liquid paint to a watercolor pan, allowing it to air dry. Â
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Dry lake pigments are ground into a powder.
Wet lake pigments go straight to the mulling stage. Allow your lake pigments to dry overnight to remove excess water before mulling. Too much water makes mulling difficult.
Making Green with Indigo:
Yellows are a common color to encounter when working with natural pigments. The varying shades of yellow can be mixed with some indigo pigment to create an incredible range of greens and teals. Â
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At the mulling stage of creating your paint, sprinkle on a few grains of indigo pigment and continue mulling.
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