Two Grade:A and B SiO2:49and30min CaO:44and40 min Fe2O30: 0.5max Whiteness:90 Mesh:100-2500 high quality Characteristic: Particle size uniformity, high purity, needle-like crystal, lowder iron content, lower oil absorption.Uaage: Mainly used in ceramic, chemical, metallurgy, construction, automobile, agriculture, etc. high quality Wollastonite Powder