Cave rainwater and groundwater charged with HCO (carbonic acid) and naturally occurring organic acids. The dissolution process produces a distinctive landform known as "karst", characterized by sinkholes and underground drainage. Limestone caves are often adorned with calcium carbonate formations produced through slow precipitation. These include flowstones, stalactites, stalagmites, helictites, soda straws and columns. These secondary mineral deposits in caves are called "speleothems". The portions of a solutional cave that are below the water table or the local level of the groundwater will be flooded. Lechuguilla Cave in New Mexico and nearby Carlsbad Cavern are now believed to be examples of another
Calcium oxide are important commodity chemicals. Calcium oxide is usually made by the thermal decomposition of materials, such as limestone or seashells, that contain calcium carbonate (CaCO; mineral calcite) in a lime kiln. This is accomplished by heating the material to above , a process called calcination or "lime-burning", to liberate a molecule of carbon dioxide (CO), leaving quicklime. The quicklime is not stable and, when cooled, will spontaneously react with CO from the air until, after enough time, it will be completely converted back to calcium carbonate unless slaked with water to set as lime plaster or lime mortar. Annual worldwide