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People have been using clay to make pottery since ancient times. However, pure silicon was not produced for the first time until 1811 by the French scientists Gay-Lussac and Thenard (L. J.), through a reaction between silicon tetrafluoride SiF4 and potassium. In 1823, Berzelius heated potassium fluorosilicate K2 with an excess of metallic potassium to produce silicon once again; he then burned the resulting silicon in oxygen to form silicon dioxide SiO2, thereby confirming that silicon is a single element. The Latin name for silicon, silicium, comes from the Latin word Silex (stone). Our country once used a transliteration for it, calling it \"xi\", but later, since \"xi\" had the same pronunciation as \"xi\", making it difficult to distinguish between the two, it was unanimously agreed in 1953 to change \"xi\" to \"gui\". Silicon is an element of group IVA in the third period, with the symbol Si. It is a major component of minerals and rocks. In nature, it does not exist in its free state but is always found in compounds, mainly SiO2 (quartz) and the silicates derived from it. Granite, for example, is composed of quartz, feldspar, and mica; quartz is a form of SiO2, while feldspar and mica are silicates. Silicon has two allotropes: amorphous and crystalline. It possesses a distinct metallic luster, is gray in color, and has a density of 2.32–2.34 g·cm-3. It features a diamond-like crystal structure, and when heated it can react with non-metals such as halogens, nitrogen, and carbon. Silicon can form only single bonds with other silicon atoms, or with carbon, oxygen, hydrogen, and halogens; it cannot form double or triple bonds, nor can it form silicon chains with more than 6 silicon atoms. Silicon can form silanes (combined with hydrogen), siloxanes (combined with oxygen), and industrially valuable siloxides (combined with oxygen and organic groups). Silicon is one of the few elements with semiconductor properties. Silicon can also react with certain metals such as magnesium, calcium, iron, platinum, etc., to form silicides. Silicon is insoluble in ordinary inorganic acids, but it can dissolve in alkaline solutions, releasing hydrogen and forming a corresponding alkali metal silicate solution. At red-hot temperatures, silicon can react with water vapor. Silicon can also dissolve in a mixed solution of nitric acid and hydrofluoric acid. Silicon is used to manufacture high-silicon cast irons, silicon steel and other alloys, silicone compounds, and silicon tetrachloride SiCl4, among others. Silicon is an important semiconductor material; silicon single crystals doped with trace impurities can be used to manufacture high-power transistors, rectifiers, and solar cells. SiO2 is a major raw material in the glass industry and is also a component of ordinary cement. Other important compounds of silicon include SiCl4, silicon carbide SiC (also known as emery), and various siloxane products. Amorphous silicon can be obtained by the high-temperature reduction of SiO2 with metallic magnesium; crystalline silicon is produced by reducing SiO2 with carbon in an electric furnace. The highly pure silicon used in the electronics industry is manufactured by reducing siltrichloride SiHCl3 or silicon tetrafluoride SiF4 with hydrogen.