What does Indigo mean?
A type of dye used to color denim to give it’s blue color. Traditionally, indigo dye was taken naturally from plants but presently the dye is produced synthetically. Each year, several thousand tons of indigo is created for denim production with each pair of denim using from 3 to 12 grams of indigo each.
Heddels explains Indigo
Indigo, whose name comes from the Greek word “Indikon” meaning “from India”, has a rich blue color and is grown primarily in equatorial climates. Indigo dye has been documented as far back as 1600 BC in India, China, and the Middle East, where it was often used as a color for royalty. Since the beginning of the twentieth century, the majority of manufactures use synthetic indigo dye, which is cheaper, stronger, and more predictable than natural indigo.
Today, almost all denim is dyed with indigo. It is unique in that the dye doesn’t actually infiltrate to the center of the fibers, but rather gathers around the core. This explains why denim fades over time, as each washing cycle removes additional specks of indigo from the fabric.
Here is a picture of indigo dye: