Hematite and magnetite iron, which is more suitable for iron smelting, why?
Magnetite (Magnetite) is an iron oxide ore, which is mainly composed of Fe3O4 and is a compound of Fe2O3 and FeO. FeO 31.03%, Fe2O3 68.97% or containing Fe 72.2%, O 27.6%, equiaxed system. The crystal body is usually eight planes, and is less rhombic than the twelve. In diamond twelve face, long diagonal line often appear stripe. The aggregates are dense, blocky and granular. The color is black, iron streak of black, semi metallic luster, opaque. Hardness 5.5 ~ 6.5, the proportion of 4.9 ~ 5.2, no cleavage, gangue mainly quartz and silicate. Having strong magnetism. Poor reducibility, generally containing harmful impurities, sulfur and phosphorus higher. In ore dressing (Beneficiation), the magnetic separation method is very convenient, but because of its fine structure, it is less reducible. After long-term weathering, it becomes hematite.
Hematite iron content is generally 50% ~ 60%, containing harmful impurities, sulfur and phosphorus less, reduction is better than magnetite, therefore, hematite is a relatively good raw material for iron smelting. Hematite has primary, there are wild, magnetite hematite after oxidation regeneration after the loss of magnetic, but still retains the crystal shape of magnetite martite, in martite often contain some residual magnetite. Sometimes hematite contains some of the weathering products of hematite, such as limonite (2Fe2O3. 3H2O). Hematite has semi metallic luster, crystalline hardness is 5.5 ~ 6, soil hematite is very low hardness, no cleavage, relative density of 4.9 ~ 5.3, only weakly magnetic, gangue silicate.
Hematite (Hematite) hematite is anhydrous iron oxide ore, its chemical formula is Fe2O3, the theoretical iron content is 70%. This kind of ore often forms huge ore deposits in nature, and it is the main ore of industrial production from the burial and mining amount. By its own structure condition is different and can be divided into many categories, such as red hematite (Red hematite), hematite (Specularhematite) (Micaceous hematite), micaceous iron and clay hematite (Red Ocher).
In nature, there are two known variants of Fe2O3, namely, alpha -Fe2O3 and gamma -Fe2O3. The former is stable under natural conditions and is called hematite. The latter is inferior to alpha -Fe2O3 in natural conditions and metastable state. It is called hematite.
