The boltonite sand (powder) is made from natural olivine ((Mg, Fe)2·SiO4) through crashing, water rinsing, screening and other procedures. It has a low expansion coefficient and strong resistance to metal oxide, no free SiO2 or silicon dust hazard. So it is an ideal molding material, especially applicable for the roughing sand and coating aggregate of high-manganese steel casting molds and cores.

Physicochemical indexes of boltonite sand (%)：

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