What kinds of lime-stone are observable at natural conditions?
Many kinds of lime-stone exist. Coquina is cluster of fragments that form cellular aggregate. Chalk is a soft crumbling staining rock, which is formed if mussels are of microscopic size. Oolite limestone consists of small (size is close to size of roe grain) mutually cemented balls. The core of such oolite ball may be either grit or mussel fragment or particle of another material. Pisolite consists of larger balls (size is close to pea size) and corresponding rock is known as pisolite limestone. The lime-stone which is formed on surface as a result of calcium carbonate precipitation from water of carboneous mineral spring. Lime-stone tuff is very porous sediment. Marl us uncemented mixture of calcium carbonate and clay.
