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Nonmetallic material, or in nontechnical terms a nonmetal, refers to materials which are not metals. Depending upon context it is used in slightly different ways. Depending upon context it is used in slightly different ways.
Most nonmetallic elements were identified in the 18th and 19th centuries. While a distinction between metals and other minerals had existed since antiquity, a basic classification of chemical elements as metallic or nonmetallic emerged only in the late 18th century.
In some cases, even organic materials and industrial products or by-products (cement, slag, silica fume) are categorized under industrial minerals, as well as metallic compounds mainly utilized in non-metallic form (as an example most titanium is utilized as an oxide TiO 2 rather than Ti metal).
This mineral group includes native metals, semi-metals, and non-metals, and various alloys and solid solutions. The metals are held together by metallic bonding, which confers distinctive physical properties such as their shiny metallic lustre, ductility and malleability, and electrical conductivity.
Non-metallic inclusions, the presence of which defines purity of steel, are classified by chemical and mineralogical content, by stability and by origin. By chemical content non-metallic inclusions are divided into the following groups: sulfides (simple — FeS, MnS, Al 2 S 3, CaS, MgS, Zr 2 S 3 and others; compound — FeS·FeO, MnS·MnO and ...
Manufacturing of nonmetallic mineral products C23 Manufacturing of medical, precision, optics and clocks C27 KRW 8 billion or less Manufacturing of other products C33 Water, sewage, and waste disposal, raw material recycling (excluding waterworks) E(excluding E36) KRW 3 billion or less Transportation and warehousing H KRW 8 billion or less
They are inorganic, non-metallic compounds that may be porous or non-porous, and their crystallinity varies widely: they may be crystalline, polycrystalline, amorphous, or composite. They are typically composed of oxides, carbides or nitrides of the following elements: silicon, aluminium, magnesium, calcium, boron, chromium and zirconium. [2]
The author writes that arsenic and antimony resemble metals in their luster and conductivity of heat and electricity but that in their chemical properties they resemble the non-metals, since they form acidic oxides and insoluble in dilute mineral acids; "such elements are called metalloids" (p. 530).