2021 Annual Meeting of Japan Association of Mineralogical Sciences (JAMS)

Presentation information

Oral presentation

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

Fri. Sep 17, 2021 2:00 PM - 4:45 PM Zoom Session 2

Chairperson:Masanori Kurosawa, Koichi Momma, Yasuyuki Banno

4:15 PM - 4:30 PM

[R1-09] Follow-up report on Chibaite from north Fossa Magna area, central Japan

*Koichi Momma1, Hiroshi Miyajima2, Norimasa Shimobayashi3, Takashi Ishibashi4, Nobuyuki Takayama5, Toshiro Nagase6, Ritsuro Miyawaki1, Satoshi Matsubara1, Akira Ijiri7, Yoshihiro Furukawa8 (1. NMNS, 2. Itoigawa City Council Member, 3. Kyoto Univ., 4. Masutomi Mus. Geo. Sci., 5. Friends of Fossa Magna Museum, 6. Tohoku Univ., Mus., 7. Kobe Univ., 8. Tohoku Univ.)

Keywords:chibaite, silica clathrate, pseudomorph, Fossa Magna

In 2013, we reported occurrence of chibaite from north Fossa Magna area, central Japan. At that time we didn’t report details of the locality to protect the outcrop from collectors. In April, 2021, the locality, silica clathrate minerals, and their pseudomorphs were designated as natural heritage of the Otari village, Nagano Prefecture, Japan. We will report follow-up story of the world’s 2nd occurrence of chibaite about geology, crystal structure, gas composition in the crystal, and carbon isotope of gas molecules.