Pegmatite.
Ref.: Yamada, S., Okamoto, A., Takada, M., Fujiwara, T., and Takemura, M. (1980) On the thortveitite, fluocerite, pyroxferroite and other minerals from the Isanago mine, Ōro, Nagagun Kyoto Prefecture. Chigaku Kenkyu: 31: 205-222 (in Japanese).
Mineral List:4 entries listed. 3 valid minerals.
The above list contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database!