Suzukura Mine
Enzan-Hirasawa, Koshu city, Yamanashi pref., Japan
Occurrence
Moderately low-T hydrothermal deposit
Combination deposit of the moderate-T hydrothermal deposit and the low-T hydrothermal deposit in the late Miocene (10 Ma) Tokuwa Granite intruded in the Paleogene Sagamiko Group of the Shimanto accretionary complex. The Tokuwa Granite is I-type (Magnetite-series) with the S-type (Ilmenite-series) margin. The S-type (Ilmenite-series) margin was formed by reduction reation of granite magma with surrounding pelitic rocks. The deposit near the I-type (Magnetite-series) core of the Tokuwa Granite is rich in arsenopyrite, and the deposit near the the S-type (Ilmenite-series) margin of the Tokuwa Granite is rich in Pb-Sb-bearing minerals. The sediments of the Sagamiko Group near this locality is probably those of the middle Eocene (45 Ma) Gongenyama Unit. Ages of sedimentary rocks were determined by radiolarians, and granite age by K-Ar radiometric dating of biotite and whole rock.
An adit of the Suzukura mine. Side walls of the adit are fresh granite of the Tokuwa Granite, and no alteration was observed. The ore body was associated with quartz veins having north to south trend.
Reported Minerals
- Galena
- Chalcopyrite
- Pyrite
- Arsenopyrite
- Boulangerite
- Bournonite
- Sphalerite
- Kaňkite(Kankite)
- Pyrrhotite
- Molybdenite
- Scorodite
- Anglesite
- Chrysocolla
- Brochantite
- Linarite
- Cerussite
- Realgar
- Realgar
Mineral Assemblages
- Quartz(Gangue) - Pyrite - Galena - Arsenopyrite - Chalcopyrite
- Quartz(Gangue) - Arsenopyrite - Scorodite
- Sphalerite - Galena(fine grained) - Pyrite(fine grained)
- Quartz(Gangue) - Calcite(Gangue)
History
- 1946: The mine was closed.
Localities
- Suzukura Mine (Granite, Fe-Pb-As)
- Nakamaru Mine (Dacite, Cu-Sb-As)
- Tsugu Mine (Andesite, Cu-Sb)