Brief Description: Its name comes either from Magnesia of Thessaly (Source: Thales of Miletus) or from the name of a shepherd that discovered the mineral on Mount Ida of Crete (Magnes), when he noticed that the nails of his shoes and the metal part of his rod stuck to the ground (Source: Plinius). Its chemical formula is Fe3O4 and it belongs to Oxides (spinel group). It is opaque, has a metallic lustre and iron black colour. Its specific gravity is 5.2 with fusibility 7 and hardness 5½ - 6½. It consists of octahedral crystals, with solid, granular aggregates. Powerfully magnetic. It occurs in black sand and as minor mineral in igneous (mainly basic) and metamorphic rocks. It is encountered with pyroxenes, biotite, feldspar, quartz, iron pyrite etc. It constitutes the primary iron ore. 
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