Clays are natural materials composed of fine-grained minerals, primarily formed from the weathering of rocks. They are characterized by their plasticity when wet, allowing them to be easily shaped, and they harden upon drying or firing. Clays are commonly used in pottery, ceramics, and construction, making them essential in various industries. There are several types of clays, including kaolin, bentonite, and illite, each with unique properties and uses. For example, kaolin is often used in porcelain and paper production, while bentonite is valued for its absorbent qualities in drilling fluids and cat litter.