1) Orthorhombic mineral 
Wadsleyite is a high-pressure polymorph of olivine, and is an orthorhombic mineral found in the Peace River meteorite in Alberta, Canada. In phase transformations with increasing pressure from Mg2SiO4-Fe2SiO4 (forsterite – fayalite), olivine is transformed to wadsleyite (β-Mg2SiO4) and then to a spinel-structured ringwoodite (γ-Mg2SiO4). This ...