New data on ferri–ghoseite in Sanbagawa quartz schist from the Iimori region, Wakayama Prefecture, Japan: solid solution between magnesio–riebeckite and clino–suenoite

Chemically heterogeneous amphibole, ranging in composition from magnesio–riebeckite through ferri–ghoseite to clino–suenoite, was found in a specimen of Sanbagawa quartz schist from the Iimori region of the western Kii Peninsula, central Japan. The amphibole exhibits a continuous solid solution between BNa and BMn2+ (BMn2+ = 0–1.82 atoms per formula unit). Most of the amphibole crystals comprise a Mn–poor core and a Mn–rich rim, and...