Tufa is a type of porous limestone that forms through the precipitation of calcium carbonate from mineral-rich waters. It typically develops in freshwater environments, such as lakes and springs, where the water's temperature and chemistry promote the deposition of minerals. Tufa can create unique geological formations, often resembling towers or mounds. This natural rock is commonly found in areas like Mono Lake in California and Lake Pavin in France. Tufa formations can provide important habitats for various plant and animal species, contributing to local biodiversity. Additionally, they are often studied for their role in understanding past environmental conditions.