Kaolin is a clay soil that consists mainly of the white-coloured, fine-grained mineral kaolinite. The name is derived from “Gaoling”, a village near Jingdezhen in southeastern China’s Jiangxi Province, and entered English in 1727 when used by a French geologist.
Kaolin is widely used in many industries, being the main raw material for the ceramic, porcelain and paper industries, an important additive for the food industry, and for making toothpaste, cosmetics, rubber, paint, white-light lamp, for example. The quality of kaolin depends on its associated impurities. From the originally white colour it can become yellowish, pinkish or reddish due to the iron oxide content. From being very fine-grained, thus suitable for high quality products or just for making lower quality pottery.
Kaolin can be of two origins, one being the hydrothermal alteration of feldspar minerals, a process called kaolinization, usually found in small but high quality mines. It can also be of sedimentary origin, i.e. by river or marine sedimentation, which usually results in large but lower quality mines.
In Vietnam, the kaolin resource is estimated at 15 million tons, distributed mainly in the provinces of North Vietnam and the Central Highlands.
The Dak Ha kaolin quarry is located in Dak Ha commune, Dak G’Long district on an area of 26.67 ha, comprising several seams of weathered claystone that alternate with layers of siltstone and sandstone. Since 2017, Cuong Thanh Co. Ltd has been licensed for mining at this quarry. After a short period of mine preparation, the first batches of kaolin powder have been mined, processed and supplied for the domestic market.