Conditions of the feldspathic raw materials supply from domestic and foreign sources in Poland

摘要: Feldspars are the most abundant group of rock-forming minerals in nature. They components many rock types, including: pegmatite, granite, syenite (especially nepheline syenite), feldspathic sand and sandstone (arkose). The major commercial value feldspars rests on their chemical composition, especially content alkalis, i.e. K2O (min. 10%) – preferred production whiteware, or Na2O 7%) glass ceramic tile manufacture. In majority applications lowest possible colouring oxides, particular Fe2O3 TiO2, is required. For example, wares high whiteness (porcelain), TiO2 cannot exceed 0.15% 0.05% respectively, while case quality max. 0.08% acceptable. term ‘feldspar raw material’ ‘feldspar’ refers to both K Na feldspar-rich grades as well feldspar-quartz ones. Poland there only latter obtained, whereas faldspathoid-rich (nepheline syenite) materials imported.