After discussing Indigo as Pigment, I’ve had a lot of requests to share the process for making Maya blue. This recipe is based on the research of Michel Garcia, whose Natural Dye Workshop DVD series I recommend. To make Maya blue pigment at home, only two ingredients and a few tools are required.
Botanical indigo powder: This can be store-bought or home processed, and must be thoroughly dry and finely ground.
Clay substrate: Sepiolite, palygorskite or attapulgite will absorb the indigo when heated. You can purchase small jars here, or larger amounts here. If your clay is granulated of foraged it must be finely ground.
Mortar and pestle for grinding: This must be dedicated to crafts only, never food.
Dust mask: These types of clay can be irritating.
Small pot: Likewise dedicated to crafting.
Mulling slab and muller: For extra finely grinding the finished pigment and mixing paint.
Make certain that none of your tools have any water on them, as even a drop will spoil the reaction. After finely grinding, weigh 10 parts clay and 1 part indigo powder. I have used 30 grams sepiolite and 3 grams indigo. Combine these in a small pot and heat over a medium low flame.
Over the course of a few minutes, you will see the two powders combine and turn a uniform blue color. At 356 degrees Fahrenheit the indigo sublimates to a gas, bypassing the liquid phase, and is immediately absorbed by the clay. Remove the pot from heat and allow to cool. The color will have a violet tinge when hot, but turn turquoise as is cools. You now have Maya blue pigment, indigo locked inside and stabilized by the clay.
A Weighed indigo and sepiolite
B Mixed indigo and sepiolite before heating
C Mixture after heating: Maya blue!
Maya blue pigment may be stored indefinitely. To use as paint it must be finely ground with a mortar and pestle followed by mulling with a binder to mix the paint of your choice. Check out Kremer Pigments and Kama Pigments course offerings and videos to learn how to prepare your own watercolor, egg tempera, or oil paints.