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Minerals, in general, are all natural mineral or rock resources buried in the ground (or distributed on the surface, or weathered by rocks, or deposited by rocks) that are available for human use. Minerals can be divided into categories such as metallic, non-metallic and combustible organic, and are non-renewable resources. Metallurgy, the process and process of extracting metals or metal compounds from minerals and using various processing methods to make metals into metallic materials with certain properties. Metallurgy has a long history of development, from the Stone Age to the subsequent Bronze Age, and then to the large-scale development of iron and steel smelting in modern times, the history of human development incorporates the development of metallurgy.

NOA provides professional services in industrial mineral inspection, steel inspection, non-ferrous metal inspection, coal and coke inspection, etc. to help the metallurgical industry and related trade.