Removing the Indigo Leaves from the Drum, After Fermentation Emptying the Drum

Indigo is a unique pigment because of its chemistry. The indigo leaves only carry the precursor to the pigment - the water soluble indican. It is after this indican has been oxidised complelety that it changes to indigotin, the actural dye pigment. This pigment is itself insoluble in water and hence requires a special technique of dyeing as well.