The world's oldest indigo-blue dyed cotton fabric - some of which is around 6,200 years old.
http://www.smithsonianmag.com/smart-new ... 180960477/
http://www.livescience.com/56099-oldest ... -peru.html
http://www.livescience.com/56093-photos ... o-dye.html
http://news.nationalgeographic.com/2016 ... ans-huaca/
http://www.ancient-origins.net/news-his ... nopaging=1