White Silica Fume, also called white microsilcia or zirconia microsilica, as a very rare micro silicon powder, is a by-product of zirconia with high SiO2. Production of zirconia requests very strict raw material and production process, so very small output of white silica fume. Because of its extreme fineness and high silica content, white silica fume is a very effective pozzolanic material. As the name denotes, it is whiter in color with reflection greater than 80%.It is the top choice of the cementitious mixtures product with high whiteness requirements.