Red powder,no odor; can’t dissolve in water, organic acid and organic solvent, but dissolvable in thick inorganic acid; stable in light, heat, air and alkali; good dispersible ability, hiding ability and strong coloring up ability. According to the particle size, iron oxide takes on different color from yellowish red and blue shade red. It can obstruct ultraviolet radiation, and can’t be absorbed by flesh, so it has none side effect. The relative density is 5.12-5.24g/mL according to the content. The melting point is 1550℃, decomposing when the temperature reach about 1560℃.