Limestone is a monomineralic rock composed of calcite and some of its admixtures. Well-known coquina is also a limestone, which consists of fragments and whole shells of ancient marine animals. There are different kinds of limestone – thinly bedded, heavy bedded, marbled. Moreover, each type of limestone has its own name by which one can immediately understand where it was found, its structure, age, and other useful data which, in turn, are important for the main consumers of limestone. Sufficiently high reliability and low cost allow limestone to stay a popular building material for centuries.