Momoiite, (Mn 2+ ,Ca) 3 (V 3+ ,Al) 2 Si 3 O 12 , an Mn 2+ -and V 3+ -rich analog of silicate garnet, was found in three localities: the Kurase (type locality), Hokkejino, and Fujii mines that are respectively located in Ehime, Kyoto, and Fukui Prefectures, Japan. Momoiite is greenish -yellow to emerald -green in color, and it occurs in the form of an aggregate having a size of up to 1 mm in a vein having a thickness of several millimeters with calcite and tephroite. Momoiite is optically isotropic, with n = 1.86(1). Its calculated density is 4.01 g/cm