micrite

Micrite is a fine-grained type of limestone composed mainly of tiny carbonate particles, known as microcrystals of calcium carbonate. It forms through the accumulation of small mineral grains, often from the remains of microscopic marine organisms or chemical precipitation in shallow seas. Micrite usually appears as a smooth, uniform mass with no visible grains, making it an important component in sedimentary rocks. It helps geologists understand ancient environments, indicating shallow, warm, and calm water conditions where fine materials could settle slowly onto the seafloor.