Magnetite is the ore of oxide mineral Magnetite, belonging to equiaxed crystal system. The crystals are Octahedron and Dodecahedron, with stripes on the crystal face, and are mostly granular aggregates. Iron black, or with dark blue indigo color, black stripes, semi metallic luster, opaque, without cleavage, uneven fracture surface, hardness of 5.5-6.5, density of 5.16-5.18g/cm3, is the most magnetic mineral and can be attracted by permanent magnets. The ancient Chinese compass "Sinan" was made using this characteristic. Crisp, odorless, tasteless. It often occurs in magmatic rocks, Metamorphic rock, and coastal sands. Distributed in Shandong, Hebei, Henan, Liaoning, Heilongjiang, Inner Mongolia, Hubei, Yunnan, Guangdong, Sichuan, Shanxi, Jiangsu, Anhui

Magnetite is widely distributed and has many origins. Kiruna, Sweden is a typical magmatic deposit. The Laco iron ore deposit in Chile is directly formed by the slurry related to Volcanism. The iron ore formed by contact metamorphism can be taken as an example by Daye Iron Mine in China. The iron ores (such as the iron ores in Anshan, China) formed by the regional Metamorphism of the sedimentary iron bearing rocks are mainly Magnetite and Hematite, which are of large scale but low grade, and are the most important source of iron ores in the world. The former Soviet Union, North America, Brazil, and Australia all have oversized iron ores of this type. Magnetite can also be enriched in river bed or coastal sand due to its large scale and resistance to weathering. It can be converted into Hematite after being oxidized; If the original shape is retained, it is called pseudo Hematite.