Tufa is a type of limestone that forms through the precipitation of calcium carbonate from mineral-rich waters, often in freshwater environments. It typically appears as porous, light-colored rock and can create unique formations, such as towers or mounds, in areas like lakes and springs. This natural phenomenon is commonly found in regions with high mineral content, such as the Mono Lake area in California. Tufa can also be associated with hot springs, where the temperature and mineral content contribute to its formation. It plays a role in the ecosystem by providing habitats for various organisms.