Limestone deposit in Nigeria is majorly deposited in Cross River and Ebonyi states but can still be found in commercial deposit in Abia, Akwa Ibom, Anambra, Bauchi, Bayelsa, Benue, Borno, Edo, Enugu, Imo, Ogun, Ondo and Sokoto, making Nigeria the most richly deposited West African country when it comes to Limestone.
This is one of the mineral deposits in Nigeria that is of great proportion but it is not renewable, and unlike some of these minerals, limestone is processed and quarried by various local and international construction companies in Nigeria.
Some of these quarrying companies include but is not limited to Rich Quarries Nigeria Limited, Crushed Rock Industries and Stonehill Nigeria Limited, as there are more than hundreds of quarrying companies in Nigeria located in the various states where it is deposited in.
Limestone is a sedimentary rock with a large composition of minerals primarily of calcium carbonate (CaCO3) in the crystal forms of calcite and aragonite; most limestone is mainly composed of some significant parts of marine organisms which can include forams, molluscs and corals.
All sedimentary rocks contain about 10% - 15% of limestone deposits with is formed from the accumulation of shell, coral, algal and faecal debris most commonly situated in clear, warm and shallow marine waters.
It is soluble in water solutions and leads to karst landscape which is mostly characterized by underground drainage systems with sinkholes and caves (most cave systems are through limestone bedrock).
The Mining of Limestone is an outdoor activity which involves the separating of the limestone rock in quarry benches and dividing it into blocks.
Limestones quarrying is of great benefit as it can be used in various applications but it also has its own disadvantages; the blasting and quarrying of limestones or other forms on sedimentary rocks in Nigeria or other parts of Africa and the world can seriously lead to a permanent disfiguration of the environment, noise pollution and disturbance from the blasting, and maybe in severe cases can even lead to earthquake due to continues shaking of the earth-crust.
Limestone has numerous uses:
· As a building material (major constituent in cement production).
· Used as a crushed stone for railroad ballast and road base.
· It is used in glass manufacturing.
· Used as a filler in paints, toothpaste and other products.
· In theproduction of lime, it is used as a chemical feedstock.
· It is also used in blast furnaces for iron purification.
· Limestone together with quicklime and slaked lime are all used to neutralise excess acidity.