Soda feldspar（Albite）is a very rich non-metallic mineral resource. You may have seen it around us. It is mainly used for making ceramics and glass. In recent years, with the development of China’s industry, soda feldspar has been used more and more widely. Understanding the chemical composition and physical properties of albite can make reasonable use of soda feldspar.
Albite is a sodium mineral of plagioclase solid solution series, most common in pegmatite and granite, also known as labradorite or amphibole, albite is sodium aluminum silicate (NaAlSi3O8), it is manufactured raw materials for glass and ceramics.
(1) Chemical composition of soda feldspar
The chemical formula of soda feldspar is Na2O · A12 O3 · 6SiO2, of which Na2O 11.8%, A12 O3 19.5%, SiO2 68.8%, the composition contains 0~10% An molecule, and often contains a small amount of KAlSi3O8. In addition, trace elements such as Sr and Ba are often found. It is difficult for the albite mineral in nature to reach its theoretical value. The closer the chemical composition of feldspar is to its theoretical value, the purer the feldspar and the better its quality.
(2) Physical properties of soda feldspar
The crystals are often in the shape of parallel plates or even blades, the latter being called phylloalbite. Sometimes it is in the form of sugar granules in the aggregate, and the granule variants are generally finer, and clearer twin crystal grains can be seen on the fresh surface. The color is white, sometimes gray, light blue, light green, light red and other colors.
Soda feldspar is contained in many rocks, and people call such minerals rock-forming minerals. Albite is a sodium mineral of plagioclase solid solution series and alkaline feldspar series. It has a tripod-like structure, and silicon and aluminum are tetrahedral coordination, forming larger vacancies (that is, lattice positions), which are mainly occupied by cationic sodium. Although all silicon and aluminum atoms occupy tetrahedral positions in this structure, the specifics of their positions vary. The distribution of silicon and aluminum atoms is highly ordered at low temperature, and the distribution of atoms is much disordered at high temperature.