INDIGO CRYSTALS(Indigofera tinctoria) aka pre-reduced indigo.
It is processed in Japan by an extraction and fermentation method, freeze-dried to make it the easiest indigo ever to use. Just add the crystals to warm water, thiox and soda ash, stir, wait a few minutes (not hours) and it’s ready to use for vat dyeing or hand-painting.
Best on cotton, linen; good on other fibers. This is a beautiful blue dye and pigment, but for manuscript illuminations, a few grains will go a very long way! Indigo in any form is very light- and wash-fast, but not abrasion resistant. Mordants will not change colors, but only affect the shades of blue that can be obtained.
AKA: Freeze-dried indigo, instant indigo, pre-fermented indigo, pre-reduced indigo, processed indigo.
Indigo (and woad) were also known as: [L] indicum, indicotic [Gk] indikon, indikos, [OE] indygo, indicoe, pastel, flory, anneill of Barbarie, indicoe of Turkey, wood, indicoe of the West Indies, indaco, [Sp] añil, azul de añil, [Ger] woad wild (any blue dye), [Gael] guirmean, [It] endego, endego de Badad, [Roman Palestine] kallianinos, indicolite (the dye, pigment, or dark blue tourmaline), [Thai] khram, [Hin] neel, reng (Indigo leaves), [Skt] nili, [Sc] lland grenewoad, [Sanskrit] neelam. [India]