R1: Characterization and description of minerals

[R1P-09] Morimotoite from Chisaka, Hidaka, Hokkaido, Japan

*Daisuke Nishio-Hamane¹, Akihito Hagiwara (1. ISSP, Tokyo Univ.)

Keywords:Morimotoite, Andradite, Hydrous garnet, Nikabira complex, Hidaka

We report new occurence of morimotoite from Chisaka, Hidaka, Hokkaido, Japan. Morimotoite occurs as the component of the chlorite-diopside rock and the vein cutting the rock. The chemical cpmposition yields the empilical formula of (Ca_2.95Mg_0.05)_Σ3(Ti_0.81Fe²⁺_0.81Fe³⁺_0.24Al_0.13)_Σ1.99[Si_2.54(H₄O₄)_0.47]_Σ3.01O_10.12. This corresponds to hydrous morimotoite.