Compare & Contrasting Gathering Blue and The Giver by Alexis Lorenc on Prezi. Indigo dye. Indigo dye is an organic compound with a distinctive blue color (see indigo).
Historically, indigo was a natural dye extracted from plants, and this process was important economically because blue dyes were once rare. Nearly all indigo dye produced today – several thousand tons each year – is synthetic. It is the blue of blue jeans. Uses[edit] What Color is Indigo and What is its Symbolism? Gathering_Blue_Interdisciplinary_Unit.pdf. Gathering-EG-2013.pdf.