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Metallurgy refers to the process and process of extracting metals or metal compounds from minerals and making metals into metal materials with certain properties by various processing methods. Metallurgy has a long history of development, from the Stone Age to the subsequent Bronze Age, and then to the large-scale development of modern steel smelting. The history of human development is fused with the history of metallurgy.

Cement, powdered hydraulic inorganic cementing material. After mixing with water, the slurry can be hardened in air or in water, and can firmly bond sand, stone and other materials together. The mixture of early lime and volcanic ash and modern lime and volcanic cement, which is used to bond the concrete made of crushed stone, not only has higher strength after hardening, but also can resist the erosion of fresh water or salt water.

Mine refers to an independent production and management unit with a certain mining boundary. The mine mainly includes one or more mining workshops (or pits, mines, open-pit stopes, etc.) and some auxiliary workshops, and most mines also include beneficiation plants (coal washing plants). The size of the mine scale should be commensurate with the economic and reasonable service life of the mine, only in this way can capital construction costs be saved.