Whiteness ≥ 60 degree,  

K-Na Feldspar is a silicate mineral rich in sodium and potassium.  It has the advantages of low melting point, long melting interval, high melting viscosity and small fluidity.  Widely used in ceramic material, electrode and other industrial sectors.  Feldspar titanium oxide <0.02%, burning vector 0.54, hardness fluctuations in 6-6.5, brittle, has high compressive strength, acid has strong chemical stability, use;  Manufacturing flat glass, glassware, high - voltage porcelain, etc.