INDIGODYE
Indigo dye
Indigo dye is an organic compound with a distinctive blue color . 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.The above text is a snippet from Wikipedia: Indigo dye
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