Silica fume, also known as microsilica, is an amorphous (non-crystalline) polymorph of silicon dioxide, silica. It is an ultrafine powder collected as a by-product during silicon and ferrosilicon alloy production. According to the SiO2 content, our products can arrange form grade 85% to grade 98%. According to the bulk density, we can divide our products into densified silica fume and undensified silica fume.