Barite is a mineral used as a white pigment and filler in products like paper, glass, and textiles. It can be milled into different mesh sizes for various applications. The YGM Raymond mill and HGM ultrafine mill are recommended for grinding barite into fine powder between 15-3000 meshes. The barite grinding process involves transporting barite into a hopper, feeding it into the grinding mill, screening the product, and recycling any undersized material back for additional grinding.