Limestone is a sedimentary rock composed of the mineral calcite (calcium carbonate) . The primary source of this calcite is usually marine organisms. These organisms secrete shells that settle out of the water column and are deposited on ocean floors as pelagic ooze (see lysocline for information on calcite dissolution). Secondary calcite may also be deposited by supersaturated meteoric waters (groundwater that precipitates the material in caves). This produces speleothems such as stalagmites and stalactites. Limestone makes up approximately 10 percent of the total volume of all sedimentary rocks.
Limestone is a sedimentary rock composed of the mineral calcite (calcium carbonate) . The primary source of this calcite is usually marine organisms. These organisms secrete shells that settle out of the water column and are deposited on ocean floors as pelagic ooze (see lysocline for information on calcite dissolution). Secondary calcite may also be deposited by supersaturated meteoric waters (groundwater that precipitates the material in caves). This produces speleothems such as stalagmites and stalactites. Limestone makes up approximately 10 percent of the total volume of all sedimentary rocks.
Uses of limestone
Limestone is quarried for roadbeds, building and landscape construction, and cement manufacture. Limestone is especially popular in architecture, and many landmarks around the world, especially in North America and Europe , are made primarily of the material. Limestone is readily available and relatively easy to cut into blocks or more elaborate carving. It is also long-lasting and stands up well to exposure. However, it is a very heavy material, making it impractical for tall buildings; it is also quite expensive. Most limestone used in construction comes from India .
Though the limestone used for construction is good for humid climates, it is vulnerable to acids, making acid rain a problem when it occurs in places where limestone is used extensively. The acids in the water can wear away the details of statues and other art.
