Introduction: Apart from many commercial uses, limestone rock allows caves to form either naturally or from excavations. The carbonate minerals dissolve easily in the acidic groundwater, which forms large underground chambers lined with cave deposits, as well as stalagmites and stalagtites. If an underground cave is exposed to the surface, a sinkhole can be formed. Limestone originally composed of the shells and remains of marine animals.
Distribution: Otavi Mountains and surrounding land.
Composition: Carbonate minerals, such as calcite and chalk.
Colouration: White, grey and buff to black and red.
Uses: Limestone is used in the manufacture of cement, as flux in the production of non-ferrous metals, sewage and water purification, stone dusting in coal mines and as a paint, rubber, wood putty, vinyl tiles and asphalt filler. Dolomite and limestone are used as fertilizers and limestone is a major aquifer that stores enormous volumes of underground water. Lead, zinc and vanadium are found in limestone.