These first three photos, on the left, are 100% cotton samples. The sample on top was dyed with acid dyes -- interesting, because dyers don't normally use acid dyes on cellulose fibers, but the results were noteworthy. Bottom line: the cotton took up the acid dyes and with steam setting, the colors are fast.
The middle sample was dyed with natural dyes (fustic, madder, cochineal and logwood gray), and mordanted for protein fibers (i.e., with alum sulfate). Still quite a bit of dye takeup even though cotton is a cellulose fiber.
This third sample was dyed with natural dyes and mordanted for cellulose fibers with alum acetate. There was even more dye takeup, as I expected with the cellulose mordant.