When folks see my dark burgundy red-colored yarn, they want to know what I used to dye it. They are then usually surprised when I tell them that the dye material is bugs. But that's really what cochineal is. Cochineal are scale insects that feed upon the prickly pear cactus fruit, which is dark pink. They are collected by hand and dried, and then sold in the form you see below:
Dried cochineal insects
To make the dye, I boil the bug bodies in several changes of water and strain them out. Once they're boiled, they look like so:
The resulting dye bath is dark red. I should be getting a true red from my cochineal when I use the alum mordant, and I'm not totally sure why mine comes out like raspberry sorbet. I'm guessing it must be our water. With its pH, I would expect to get a true red, but there are likely dissolved minerals, which may alter the outcome. One of these days, I'll try it with distilled water or rainwater, and see if I get different results. I have also seen instructions that recommend grinding the cochineal before extraction. I wonder if this would yield more red? I'm not really disappointed though, because this shade of purple-red-raspberry is one of my favorites.
Cochineal-dyed fingering-weight yarn