Chromium Sand is a special sand for casting. It is a kind of natural spinel mainly made of chromite. Chromite ore is divided into 2 grades by chemical composition. Level 1 Cr2O3 45% or more; The secondary Cr2O3 35% or higher. Chrome iron sand is mainly used for surface sand of large steel castings in casting production to prevent the surface sand of castings from sticking. Secondly, it is used for refractory aggregate of casting coating. Chromium iron ore is a cold material, in the molding (core) can replace part of the cold iron.