This mano and metate is covered in cochineal. Cochineal is a parasitic insect that lives in cactus leaves and happens to make this bright red color when they are squished.
Gardens of nopal, or prickly pear cactus are grown just to grow and harvest these critters for the use of making red dye.
Travis S. 28 months ago | reply
This was used for somebody's thesis on Cochineal: A Bright Red Animal Dye.