Title: Olivine–Spinel Transition on Nickel Orthosilicate
Abstract: THE pressure-induced transition of olivine to a denser spinel structure is probably of considerable importance in the Earth's mantle1. Olivine–spinel transitions are known in Mg2GeO4 (refs. 2 and 3) and Fe2SiO4 (ref. 1), while a variety of evidence indicates that Mg2SiO4 will undergo a similar transition around 125,000 atmospheres and 600° C. (refs. 1 and 3). These results suggested the desirability of exploring for olivine–spinel transitions in other substances which normally crystallize with an olivine structure.