... 3.4-5.0% 2. Whiteness:90 3.Application: ceramics 4. Size:20-2500mesh potash feldsparWe are mines owner and ... glassmaking, ceramics, and to some extent as a filler and extender in paint, plastics, and rubber. In glassmaking, alumina from ... feldspar improves product hardness, durability, and resistance to chemical corrosion. In ceramics, the alkalis in feldspar ...