Brown fused alumina is a type of synthetic abrasive material that is made by fusing bauxite with other materials in an electric arc furnace. It has a high hardness and durability, making it suitable for various industrial applications. 
The main uses of brown fused alumina are:
•  As an abrasive material for sandblasting, grinding, and cutting.
•  As a refractory material for lining furnaces and other high-temperature equipment.
•  As a ceramic material for producing shaped or unshaped products.
•  As a coating material for metal preparation, laminates, and paintings.

There are different content of the BFA, sucha as 95%,90%,85&, 80% and even lower percentage.
The higher the percentage, the higher the purity and the hardness of the material. This may affect the color, the size, and the use of the material.
Brown fused alumina 95% has a white or off-white color, while Brown fused alumina 90% has a brown or tan color. This is due to the impurities present in the material, such as titanium oxide and iron oxide.
Brown fused alumina 95% is used primarily in high-performance grinding wheels and cutting tools, while Brown fused alumina 90% is used in grinding wheels, sandpaper, and other abrasive products. The higher the purity, the higher the abrasion resistance of the material.
Brown fused alumina 95% has a hexagonal crystal structure, while Brown fused alumina 90% has a trigonal crystal structure. The different crystal structures may affect the size and shape of the particles.