The mineral known as a sedimentary rock is limestone. Limestone primarily consists of calcium carbonate and forms from the accumulation of sediment, particularly the remains of marine organisms like coral and shellfish, over millions of years. It is commonly found in various geological settings, including shallow marine waters and around coral reefs. Limestone can vary in color and texture, ranging from chalky white to dark gray. It has significant economic importance, being used in construction, the manufacturing of cement, and as a chemical feedstock. Its fossils also provide valuable insights into Earth's historical environments.