... % K2O: 3.4-5.0% 2. Whiteness:90 3.Application: ceramics 4. Size:20-2500mesh potash feldsparWe are mines owner and ... quantity.Feldspar is a common raw material used in glassmaking, ceramics, and to some extent as a filler and extender in ... improves product hardness, durability, and resistance to chemical corrosion. In ceramics, the alkalis in feldspar (calcium oxide, potassium oxide, and sodium ...