Bentonite is a nonmetallic mineral with montmorillonite as the main mineral composition. The montmorillonite structure is a 2:1 type crystal structure composed of two silica tetrahedrons and a layer of aluminum oxide octahedron. Because the layered structure formed by the montmorillonite crystal cell has some cations, such as Cu, Mg, Na, K, etc., and the interaction between these cations and the montmorillonite crystal cell is very unstable, easy to be exchanged by other cations, so it has good ion exchange ability. It has been applied in more than 100 departments in 24 fields of industrial and agricultural production abroad, with more than 300 products, so people call it "soil".

    Bentonite is also called porphyry, bentonite or bentonite. Bentonite has a long history of development and use in China. It was originally only used as a detergent. (There were open-pit mines in Renshou area of Sichuan hundreds of years ago, and the local people called bentonite clay powder). It has only been used for more than 100 years. The early discovery in the United States is in the ancient strata of Wyoming, where yellow-green clay can expand into paste after adding water. Later, people called all clays with this property bentonite. In fact, the main mineral component of bentonite is montmorillonite, with a content of 85-90%. Some properties of bentonite are also determined by montmorillonite. Montmorillonite can be in various colors, such as yellow-green, yellow-white, gray, white, and so on. It can be dense block or loose soil. It feels slippery when rubbed with fingers. The volume of small block expands several times to 20-30 times after adding water. It is suspended in water, and it is paste when there is little water. The properties of montmorillonite are related to its chemical composition and internal structure.