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

[R1P-11] Mangano-mangani-ungarettiite from Tanohata mine, Iwate Prefecture, Japan

*Daisuke Nishio-Hamane¹, Koichi Momma², Masayuki Ohnishi, Norimasa Shimobayashi³, Tetsuo Minakawa⁴, Hanako Okada⁴, Hiroyuki Imai (1. ISSP, Univ. of Tokyo, 2. Nat’l. Mus. Nat. Sci, 3. Kyoto Univ., 4. Ehime Univ.)

Keywords:mangano-mangani-ungarettiite, amphibole, Tanohata mine

During the investigation for reddish black amphibole reported as mangano-ferri-eckermanite (formerly known as kozulite) obtained from the Tanohata mine, Iwate Prefecture, Japan, we found mangano-mangani-ungarettiite (MMU). Moreover, mangano-mangani-substituted form of eckermanite (MME) was also found. Both amphiboles were identified by chemical analyses, single crystal X-ray diffraction, and powder X-ray diffraction. It is difficult to distinguish between the two by appearance, but there is a characteristic that MMU < MME with respect to unit cell volume.