Characteristics and rational development and utilization of a world-class ball clay deposit in the Nanning area, Guangxi

Abstract：The Weiluo ball clay deposit occurs in the Pleistocene in the Nanning area, Guangxi. It has been proven a large clay deposit with reserves of more than two million tons by Guangxi No. 4 Geological Party. The ball clay consists of disordered kaolinite, mostly occurring as pseudo-hexagonal flaky kaolinite deposited as colloidal sediments in lake and bog basins. It is unconsolidated or not recrystallized, showing a high degree of ordering and high cohesiveness. The ball clay is very fine in grain size, being 0.94 μm on the average. The index of plasticity is up to 47-53 and the refractoriness is up to 1 750-1 790 ℃. The average content of kaolinite in the clay layers is 89%-94%, higher than that in ball clay deposits in Britain and the United States. The ball clay has large reserves and easily open-mined； so it is the best of this kind in China and comparable to the high-quality ball clay mined in Britain and the United States. However, it is being mined by the local people using the indigenous method for refractory material uses. It should be mined on a large scale with the modern techniques and sold as high-tech fillers and coating materials to supply domestic and international markets.