Pyroxferroite: Stability and X-ray Crystallography of Synthetic Ca 0.15 Fe 0.85 SiO 3 Pyroxenoid

Abstract
Synthetic Ca0.15Fe0.85SiO3 pyroxenoid has the same (pyroxmangite) structure and very nearly the same composition as pyroxferroite, a new mineral found in Apollo 11 lunar samples. The synthetic material is not stable below pressures of approximately 10 kilobars. It appears likely that the lunar pyroxferroite has persisted in a metastable state for some billions of years.