... mines owner and manufacturer of Feldspar and Quartz. We are available with Sodium Feldspar, Potash Feldspar And Quartz. We are having ... paint, plastics, and rubber. In glassmaking, alumina from feldspar improves product hardness, durability, and resistance to chemical corrosion. ... In ceramics, the alkalis in feldspar (calcium oxide, potassium oxide, and sodium oxide) act as a flux, lowering ...