Oldest indigo-dyed fabric found

Long before Egyptians, Peruvians made blue-hued cotton 6,000 years ago

patch of cloth with blue yarn

TRUE BLUE  A strand of blue yarn from a 6,200- to 6,000-year-old patch of woven cotton (right) excavated in Peru contains the oldest evidence in the world of the colorfast dye known as indigo blue, researchers say. Diagram at left denotes parts of the recovered material containing blue dye. 

Lauren A. Badams, J. Splitstoser  

Ancient South Americans made blue fabrics to dye for.