Indigo, genuine, pieces

Indigo is an organic blackish-blue pigment. A variety of plants provide the indigo dye, such as Indigofera species or Isatis tinctoria. Indigofera species can be found all over the world. The dye is obtained from a special processing of the plants’ leaves. They are soaked in water and fermented in order to convert the glycoside indicant which is naturally present in the plant into the blue dye idigotin. The precipitated product is mixed with a strong base such as lye and then pressed into cakes, dried and pulverized. This powder is then mixed with various other substances to produce different shades of blue and purple. Indigo belongs to the oldest dyes to be used for textile dyeing. The Romans used indigo as a pigment in painting, for medicine and cosmetics. It was a luxury item that was imported from India into the Mediterranean by Arab merchants. Today, indigo is also produced synthetically and available in various shades.