Magnesia-chrome bricks use high-quality sintered magnesia and chromite (Cr203 30%-15%, CaO 1%-5%) as the main raw materials. The production process of magnesia-chrome bricks is roughly similar to that of magnesia bricks. Non-fired magnesia chrome bricks use inorganic magnesium salt solution as a binder. During the firing process, due to the loosening effect caused by the expansion of spinel when MgO reacts with CrO3, Al2O3 or iron oxides, pre-synthesized magnesia sand can be used to make bricks, which must be fired in an oxidizing atmosphere above 1600 ° C. become. If the nature of the atmosphere changes, Fe203 in chromite is affected by the redox reaction to form iron oxides of various valences. At the same time, Cr203 is also reduced to produce different valence compounds. Under repeated reactions, bricks will be damaged, so products with high MgO and low Cr2O3 should be used as much as possible.