Feldspar series are versatile fillers used in coatings and plastics. They are produced by careful sieving and processing. Use of feldspar is the reason why ceramics have excellent acid & alkali resistance, weatherability, scratch resistance, hardness and durability. Feldspar series are the very products developed from the above theory, which are not soluable in acid or alkali. The stable and anti-corrosive ingredients Na(Si3O8), K(AlSi3O8), NaAl2(AlSi3010)(OH,F)2/KAl2(AlSi3O10)(OH, F)2 perform great weatherability in coating. Benefit from the crystal structure, they have high hardness and pressive strength in coatings. Respirable quartz of less than 1% makes them ideal environment-friendly fillers. All these contribute to their wide application in multi-funtional anti-corrosive coatings that are environment-friendly, high-performance and low-cost.