Clays have an enormous relative surface area and are thus highly absorbent, and can be used to draw out excess oil, impurities, toxins, and bacteria on the skin and in the pores (3). Clays also encourage dead skin cells to slough off, leaving the skin feeling smooth, clean, and refreshed. Clays have also been studied extensively for their antibacterial properties and can be effective in treating skin infections caused by antibiotic-resistant bacteria (4). These antibacterial properties contribute to their ability to help control blemishes and breakouts when used topically. (from The Curious Coconut)