The brown corundum sand is made from bauxite through high-temperature smelting. With α-Al2O3 as the basic mineral, the brown corundum has a strong hardness, high melting point and high rate of thermal conductance. At a high temperature, the brown corundum does not change or crack. It is resistant to both acid and alkaline. It is applicable for the facing sand and cores of steel castings, and the shells of investment casting and coating of molds. Additionally, it can be used as rough and free grinding materials of plain carbon steel, alloy steel, hard bronze and iron castings.
Physicochemical indexes (%):

Common granularity: 40-70mesh, 50-100mesh, 70-140mesh, 200mesh, 320mesh.