Crystal structure analysis of Mg analogue of nakauriite from Hokubo, Okayama, Japan

Abstract

Nakauriite was found with calcite, magnetite, aragonite in a crack of serpentinite at Hokubo, Okayama, Japan. Though the XRD data was the same as that from Nakauri, nakauriite from Hokubo contains little sulfur, and Mg is more than Cu. For the diffraction intensity data obtained using the expected lattice constant, attempted to derive the structure using the charge flipping method. As a result, it was suggested that nakauriite is a structure in which the MgO₆octahedral layer arranged parallel to the (010) plane is stacked at intervals of about 7.3 A through interlayer CO₃or H₂O.