Tourmaline is a general term for tourmaline minerals. It has a more complex chemical composition and is a cyclic mineral silicate mineral of aluminum, sodium, iron, magnesium, and lithium containing boron. hardness of tourmaline is usually 7 ~ 7.5 , and its density is slightly different for different types .
Tourmaline has unique properties such as piezoelectricity, pyroelectricity, far infrared radiation, and negative ion release. It can be combined with other materials through physical or chemical methods to produce a variety of functional materials. Chemical industry, light industry, building materials and other fields.