Limestone is a sedimentary rock, made up mostly of the mineral calcite, a form of calcium carbonate, CaCO3. The calcium carbonate is originally produced by living animals (such as shellfish). Later, much of it goes into solution in sea water, and then is deposited as limestone. Calcium carbonate gets precipitated when the physical condition of the water changes. For example, if the concentration of CaCO3 is high, then a temperature drop, or a pH (acidity) change, can cause precipitation. It is generally used as limestone tiles, limestone slabs in flooring, wall cladding, vanity tops and to pave the floors of large commercial complexes, hospitals, airports, shopping malls, railway stations, parks etc. It is used to make glass and cement. It can be used like chalk, as it is mostly calcium, so you can actually draw with the stone. It is also used to make iron in a blast furnace, to remove impurities from the iron ore.

Limestone is a sedimentary rock, made up mostly of the mineral calcite, a form of calcium carbonate, CaCO3. The calcium carbonate is originally produced by living animals (such as shellfish). Later, much of it goes into solution in sea water, and then is deposited as limestone. Calcium carbonate gets precipitated when the physical condition of the water changes. For example, if the concentration of CaCO3 is high, then a temperature drop, or a pH (acidity) change, can cause precipitation. It is generally used as limestone tiles, limestone slabs in flooring, wall cladding, vanity tops and to pave the floors of large commercial complexes, hospitals, airports, shopping malls, railway stations, parks etc. It is used to make glass and cement. It can be used like chalk, as it is mostly calcium, so you can actually draw with the stone. It is also used to make iron in a blast furnace, to remove impurities from the iron ore.