Red

Cochineal is a scale insect and is found on prickly pear cactus. A rasping, sucking insect, it feeds on the tasty juices of the cactus. It produces a cottony white covering to protect itself from predators.

Go to link below to see images and read about cochineal history.

Cochineal Red: The Art History of a Color  

Published on Aug 4, 2013  

Elena Phipps The Metropolitan Museum of Art Bulletin, Winter 2010 Volume LXVII, Number 3 Copyright © 2010 by The Metropolitan Museum of Art, New York

https://issuu.com/metmuseum/docs/cochineal_winter_2010_bulletin/25

Source:

https://en.wikipedia.org/wiki/File:Indian_collecting_cochineal.jpg

And also appears here:

https://www.npr.org/sections/thesalt/2012/03/30/149700341/food-coloring-made-from-insects-irks-some-starbucks-patrons

I found image here: 

http://www.pysanky.info/Natural_Dyes/Insect_Dyes.html

Would like to know true source. 

Source:

http://nathistoc.bio.uci.edu/hemipt/Dactylopius.htm

A form of communication in Inca Empire. 

Colored knots and cords. 

A model of khipu knots, representative of many khipus from pre- and post-Conquest Peru JON CHASE/ PRESIDENT AND FELLOWS OF HARVARD COLLEGE

Khipu or quipu

(kē′po͞o)

[American Spanish, from Quechua khipu, knot.]

A khipu on display at Los Angeles County Museum of Art.

Source:

https://www.atlasobscura.com/articles/khipus-inca-empire-harvard-university-colonialism

British Redcoats

Image Source:

https://en.wikipedia.org/wiki/File:Uniform_-_Private_-_37th_Regiment_of_Foot_%281742_Cloathing_Book%29.jpg

Photos on processing cochineal and foods that contain the dye. 

https://www.businessinsider.com/how-cochineal-insects-color-your-food-and-drinks-2012-3