Overview
Limestone is the raw material of cement, and it is the mineral behind Nigeria's largest non-oil industrial plants. Deposits in the south and centre of the country have supported cement and lime works for more than half a century, including major works in Ogun and Cross River states.
Where it's found
Substantial deposits occur at Ewekoro and Sagamu in Ogun State in the south-west, at Mfamosing near Calabar in Cross River State, and in the Benue valley and central belt, including parts of Benue, Kogi and Sokoto states. Some deposits are quarried alongside clay and shale, the other cement ingredients.
History of exploitation
Small-scale burning of limestone for lime is long established. Industrial cement manufacture began in Nigeria in the late 1950s and expanded through the 1960s and 1970s, with works at Nkalagu in what is now Ebonyi State, at Ewekoro in Ogun State and later at Mfamosing in Cross River State. Further plants and expansions followed in the decades after, making cement one of the country's more durable manufacturing industries.
Economic role
Cement made from domestic limestone supplied the building boom of the post-independence decades and remains a significant manufacturing employer. No current capacities or figures are given here.
Environmental and social impact
Limestone quarrying is open-cast and changes the landscape permanently, and cement works generate dust and require large volumes of energy and water. Communities near quarries have raised concerns about dust, blasting, land acquisition and farmland loss. Rehabilitation of worked-out quarry faces is partial.