Indigo powder is organic cosmetic that used in all forms of indigo dyeing for its ability to create a dark blue color. When you buy indigo powder, it’s usually in large chunks or lumps, and must be ground down into a powder before use. You can do this with a mortar and pestle or by buying a special grinder. It’s better to start with a small amount of powder — less than the size of your pinky fingernail — because it’s easy to add more if needed later on.
Indigo powder is a pigment that comes from the leaves of the plant, indigofera tinctoria. Indigo powder is more expensive than synthetic indigo dye and is derived from natural sources. It is used in both textile printing and as a coloring agent for paints, plastics, and paper. Indigo powder does not dissolve in water but can be dissolved in ethanol, glycerol, and other organic solvents.
The indigo pigment was first obtainable by extracting it from the dried plants and then grinding them into a fine powder. The present process of extracting the pigment from the plants uses an alkaline hydrolization process that heats the plants in an alkaline solution at high pressure until the dye is released from them. The liquid is then filtered through charcoal to remove any impurities and then acidified with sulfuric acid to produce a solution of indigo dye that can be used for textile printing or other industrial applications.
To make indigo powder, take two cups of dried indigo leaves and place them in a glass pot. Add two cups of water to the pot and stir gently. The water should be lukewarm, but never hot.
Tightly cover the pot with a lid and let it sit overnight. In the morning, strain the blue liquid from the leaves. Mix one teaspoon of this liquid with one cup of vinegar, add a little salt and heat it up until it boils. Simmer for 10 minutes and then remove from heat. This will give you about three ounces of indigo powder.
Store your indigo powder in a jar or airtight plastic bag to keep it fresh for up to two years. This can be used as paint or ink to create art on paper or cloth.
Indigo powder is very easy to use. Just add 1-2 pinches of indigo powder to the warm bath water and mix. Some people choose to mix it with a few drops of coconut or olive oil to help the powder dissolve better, but this is not necessary.