High Quality Content by WIKIPEDIA articles! Wadsleyite is a high-pressure polymorph of olivine, an orthorhombic mineral found in the Peace River meteorite in Alberta, Canada. In the phase transformations from Mg2SiO4-Fe2SiO4 (forsterite-fayalite), olivine is transformed to wadsleyite ?-Mg2SiO4 and then to a spinel-structured ?-Mg2SiO4 with increasing pressure. This series of transformations is thought to occur during an extraterrestrial shock event on the earth. With a formula of (Mg,Fe2+)2(SiO4), its cell parameters are as follows: a = 5.7A, b = 11.7A and c = 8.24A. It is polymorphous with ringwoodite and is found to be stable in the transition zone of the Earth’s upper mantle. These regions are between 400 and 525km in depth. Because of oxygens not bound to silicon in the Si2O7 groups of wadsleyite, it leaves oxygens unoccupied, and as a result, these oxygens are hydrated easily. As a result, there are high concentrations of hydrogen atoms in the mineral. Hydrous wadsleyite is a...