Calcium chloride is an inorganic salt that can be derived from limestone or obtained by purification from brine. It is a white, crystalline solid at room temperature that is highly soluble in water. In cosmetics and personal care products, calcium chloride functions as a cosmetic astringent. Astringents have a constricting and drying effect when applied to the skin. They work by cross-linking with proteins in the skin known as keratins, creating an invisible film that can temporarily degrease skin, tighten and tone skin, and minimize the appearance of enlarged pores. Calcium chloride can also be used as a viscosity increasing agent. The term viscosity corresponds to the concept of “thickness”, for example, honey has a higher viscosity than water. Therefore, as a viscosity-increasing agent, calcium chloride works to thicken formulations in order to make a product less runny and easier to spread.