Hostname: page-component-586b7cd67f-2brh9 Total loading time: 0 Render date: 2024-11-22T05:14:52.888Z Has data issue: false hasContentIssue false

Minohlite, a new copper-zinc sulfate mineral from Minoh, Osaka, Japan

Published online by Cambridge University Press:  05 July 2018

M. Ohnishi*
Affiliation:
12-43 Takehana Ougi-cho, Yamashina-ku, Kyoto 607-8082, Japan
N. Shimobayashi
Affiliation:
Department of Geology and Mineralogy, Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan
D. Nishio-Hamane
Affiliation:
The Institute for Solid State Physics (ISSP), The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581, Japan
K. Shinoda
Affiliation:
Department of Geosciences, Faculty of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan
K. Momma
Affiliation:
Department of Geology and Paleontology, The National Museum of Nature and Science, 4-1-1 Amakubo, Tsukuba, Ibaraki 305-0005, Japan
T. Ikeda
Affiliation:
Research Center for Compact Chemical System, National Institute of Advanced Industrial Science and Technology (AIST), 4-2-1 Nigatake, Miyagino-ku, Sendai, Miyagi 983-8551, Japan
*

Abstract

Minohlite, a new copper-zinc sulfate mineral related to schulenbergite, was found in the oxidized zone of the Hirao mine at Minoh (Minoo) City, Osaka Prefecture, Japan. The mineral occurs in cracks in altered shale as rosette aggregates up to 100 m m in diameter, composed of hexagonal platy crystals up to 50 μm m in diameter and 10 μm m in thickness. The associated minerals are chamosite, muscovite, smithsonite, serpierite, ramsbeckite, 'limonite' and chalcopyrite. Minohlite has hexagonal (or trigonal) symmetry with unit-cell parameters of a = 8.2535(11), c = 8.1352(17) Å, V = 479.93(16) Å3 and Z = 1, and possible space groups P6, P, P6/m, P22, P6mm, P2m and P6/mmm (or P3, P3, P321, P3m1, Pm1, P312, P31m and P1m). The six strongest reflections in the powder X-ray diffraction pattern [d in Å (I) hkl] are 8.138 (20) 001; 4.128 (24) 110; 2.702 (100) 120; 2.564 (76) 121; 1.560 (43) 140; and 1.532 (24) 141. Electron microprobe analyses gave the following values (wt.%): CuO 37.18, ZnO 21.08, FeO 0.49, SO3 16.78, SiO2 0.44, and H2O 24.03 (by difference). The empirical formula, calculated on the basis of Cu + Zn + Fe + S + Si = 9 atoms per formula unit, is (Cu4.43Zn2.45Fe0.06)Σ6.94[(SO4)1.99(SiO4)0.07]Σ2.06(OH)9.64·7.81H2O, which leads a simplified formula of (Cu,Zn)7(SO4)2(OH)10·8H2O where Cu > Zn. The mineral is bluish-green and transparent with a pearly to vitreous lustre. The streak is pale green. Cleavage is perfect on {001}. The Mohs hardness number is less than 2. The calculated density is 3.28 g cm−3. The mineral is named after Minoh City, where it was discovered.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2013

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Matsuura, H., Kurimoto, C., Sangawa, A. and Bunno, M. (1995) Geology of the Hirone district. With Geological Sheet Map at 1:50,000. Geological Survey of Japan [in Japanese with English abstract].Google Scholar
Mumme, W.G., Sarp, H. and Chiappero, P.J. (1994) A note on the crystal structure of schulenbergite. Archives des Sciences (Gene`ve), 47, 117124.Google Scholar
Ohnishi, M., Shirakami, M. and Yoshimura, T. (2001) Secondary minerals from the Hirao Old Mine, Onsen-cho, Minoo City, Osaka Prefecture, Japan. Chigaku Kenkyu, 50, 137–159. [in Japanese].Google Scholar
Ohnishi, M., Kobayashi, S. and Kusachi, I. (2002) Ktenasite from the Hirao mine at Minoo, Osaka, Japan. Journal of Mineralogical and Petrological Sciences, 97 (Sueno Issue), 185189.CrossRefGoogle Scholar
Ohnishi, M., Kobayashi, S., Kusachi, I., Yamakawa, J. and Shirakami, M. (2004) Ramsbeckite from the Hirao mine at Minoo, Osaka, Japan. Journal of Mineralogical and Petrological Sciences, 99, 1924.CrossRefGoogle Scholar
Ohnishi, M., Kusachi, I., Kobayashi, S. and Yamakawa, J. (2007a) Mineral chemistry of schulenbergite and its Zn-dominant analogue from the Hirao mine, Osaka, Japan. Journal of Mineralogical and Petrological Sciences, 102, 233239.CrossRefGoogle Scholar
Ohnishi, M., Kusachi, I. and Kobayashi, S. (2007b) Osakaite, Zn4SO4(OH)6·5H2O, a new mineral species from the Hirao mine, Osaka, Japan. The Canadian Mineralogist, 45, 15111517.CrossRefGoogle Scholar
Ohnishi, M., Shimobayashi, N. and Miyawaki, R. (2010) Cu-rich schulenbergite from the Nii mine, Hyogo Prefecture, Japan. Abstracts for 2010 Annual Meeting of Japan Association of Mineralogical Sciences, p. 88.Google Scholar
Seto, Y., Nishio-Hamane, D., Nagai, T. and Sata, N. (2010) Development of a software suite on X-ray diffraction experiments. The Review of High Pressure Science and Technology, 20, 269276. [in Japanese with English abstract].CrossRefGoogle Scholar
von Hodenberg, R., Krause, W. and Täuber, H. (1984) Schulenbergit, (Cu,Zn)7(SO4,CO3)2(OH)10·3H2O, ein neues Mineral. Neues Jahrbuch für Mineralogie, Monatshefte, 1724. [in German with English abstract].Google Scholar