Feldspar comprises a group of minerals containing potassium, sodium, calcium & aluminum. They are the most common rock-forming minerals. The common feldspar is potassium feldspar, namely, orthoclase (K [AlSi3O8]), sodium feldspar, is albite (Na[AlSi3O8]) and calcium feldspar is anorthite(Ca[AlSi3O8]).Potash and soda feldspar occur as essential constituents of granite, syenite and gneisses. Workable deposits are found in pegmatite veins consisting mainly of feldspar, quartz-feldspar veins and also occur with mica pegmatite.