South Africa chromite sand casting South Africa chromite sand casting , Originally from South Africa ,is a special kind of sand for casting , chromite sand casting is a natural spinel mainly composed of chromite , Chromite sand casting used as a highly fireproof sharpener for moulds and cores. Purpose 1 foundry industry Its properties enable the material to be used in high duty grey iron and steel foundries as core and mould making sand. 2 steel industry In steel production, Chromite Sand Casting is used as well filler for protection of the sliding gate in large steel holding ladles. 3 glass industry When ground to a fine flour, Chromite Sand casting is used for the production of green glass beverage containers