R1: Characterization and description of minerals (Joint Session with The Gemmological Society of Japan)

[R1-10] Mn-dominant variety of tetrahedrite from Teine mine, Hokkaido

*Koichi Momma¹, Masaaki Shimizu², Yoko Kusaba¹, Yoshiya Ohki³ (1. NMNS, 2. Hokuriku Polytechnic College, 3. Nippon Chigaku Kenkyu-kai)

Keywords:tetrahedrite group, tetrahedrite, tennantite, Teine mine

General formula of tetrahedrite group minerals can be written as M(2)₆M(1)₆X(3)₄S(1)₁₂S(2) (Z = 2). Nomenclature of this group has been changed in 2020 to take into account the most dominant divalent cation. We recently discovered Mn²⁺ dominant variety of tetrahedrite from Teine mine, Hokkaido, Japan. Crystal structure refinement of single-crystal X-ray diffraction data converged to R1 = 0.0098. Mn²⁺ was confirmed to occupy part of the M(1) site, as is the case of other divalent cations in tetrahedrite and tennantite.