Chrysotile
Mg3(Si2O5)(OH)4
Chrysotile is a form of serpentine. Serpentine is formed by low-temperature hydration of the magnesium silicates olivine, pyroxene and amphibole, and describes a group of minerals with a composition approximating H4Mg3Si2O9. The polymorphic forms of serpentine are chrysotile, a type of asbestos which are based on a sheet of linked SiO4 tetrahedral joined to a brucite layer such that two thirds of hydroxyl (OH) groups are replaced by silicon-bonded oxygens. The serpentine structure, which is built on tri-octahedral brucite, may be compared with kaolinite, which has di-octahedral gibbsite layers.
The dimensions of the brucite and SiO4 sheets do not match exactly resulting in curved crystal structures. Chrysotile show crystallographic and structural evidence for curved structures. In fibrous chrysotile, the mismatch results in continuous bending into cylindrical tubes.
Chrysotile is the form of asbestos from the serpentine group that has been used commercial.There is some evidence that this form of asbestos is not as harmful when inhaled. In the United States, chrysotile has been the most commonly used type of asbestos. Chrysotile is often present in a wide variety of materials, including but not limited to:
