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Glass can be machined on a lathe with glass-hard steel cutters, turning out shaped pieces in the same way as from wood or metal. Glass is ground and polished using usual abrasive powders, tools, and methods that have long been known and widely used in the metalworking industry.

Glass Grinding
Glass Grinding
Glass can be founded from single silica sand which chemical formula is SiO2. However, this requires a very high temperature (above 1700° C). Obtaining such temperatures in industrial-type furnaces is associated with great difficulties. Usual furnaces that use solid, liquid or gaseous fuels are not suitable for this. For the melting of quartz sand, electric furnaces of special device or burner are used, in which hydrogen is burned in a stream of oxygen. Molten quartz sand is such a thick and viscous mass that it is difficult to remove air bubbles from it and give the desired shape to the products.

Glass Machining
Glass Machining
In glassmaking, only the purest varieties of quartz sand are used, in which the total amount of pollution does not exceed 2–3%. Especially undesirable is the presence of iron, which even in insignificant quantities (tenths of a percent) colors the glass in a greenish color. If soda (Na2CO3) is added to the sand, then it is possible to found the glass at a lower temperature (200 - 300° lower). Such a melt will be less viscous (bubbles are easier to remove, and products are easier to form). But! Such glass is soluble in water, and products from it are subject to destruction under the influence of atmospheric effects. To make the glass insoluble in water, a third component is brought in it - lime, limestone or chalk. All of these three substances are characterized by the same chemical formula - CaCO3.

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