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The Major raw materials for manufacture of pottery are kaoliny and the clay, applied in the pure state, and more often - in a mix with additives (otoshchajushchimi, poroobrazujushchimi, plavnjami, softeners, etc.). Under kaolinami and glinami understand natural water aljumosilikaty with the various impurity, capable at zameshivanii with water to form the plastic dough which after roasting is irreversible passes in kamnepodobnoe a condition.
Kaoliny. Kaoliny consist almost exclusively of a mineral kaolinita (Al2O3-2SiO2-2H2O) and contain a significant amount of particles less than 0,01 mm; after roasting keep white or nearly so white colour.
Clay. Sharp differentiation between kaolinami and glinami it is impossible to spend. Some clay (for example, fire-resistant) are close to kaolinam on structure and properties. Nevertheless clay more.raznoobrazny on mineral structure, they are more polluted by mineral and organic impurity. clay substance (with particles 0,005 mm there are less) consists mainly from kaolinita and related to it of minerals - montmorillonita (Al2Cv4Si02X HpN2O), galluazita (Al2O3-2SiO2-4H2O), etc. Tonkodispersnye water silicates of alumina are in crystal and partly kolloidalnoj forms. Presence in glinah mineral kolloidov in the form of untied А12О3 and SiO2 with a variable quantity of water, and also kolloidalnyh organic substances, for example gumusa is possible.
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