Vermiculite is a layered structure of magnesium aluminum silicate secondary water metamorphic minerals, ore outside like mica, usually by black (K) mica by hydrothermal alteration or weathering, because heat loss deflection was like, when inflated shape resembles leech, it said vermiculite. Vermiculite has the formula M g × (H2O) [Mg3 × (AlSiO3O10) (H2O)] chemical composition: Molecular SiO2 MgO Al2O3 Fe2O3 H2O CaO PH name alumina silica-magnesia three ferric oxide, calcium value of water content% 37-4211-239-17 3.5 to 15 5-111-27-1 vermiculite press phased into the vermiculite ore and vermiculite expansion, by color can be divided into golden vermiculite, silvery white vermiculite stone, white vermiculite. Vermiculite ore roasting at high temperatures the rapid expansion of its volume can be 8-20 times the proportion of the expanded 130-180kg / m3, with strong thermal insulation properties.