Shintani Mine
Yozawa, Akiruno city, Tokyo, Japan
Occurrence
Low-T zeolite facies bedded manganese deposit
Bedded manganese deposit in mudstone matrix of the Early Jurassic Unazawa Unit, a member of accretionary complex, Southern Chichibu Belt.
Outcrop of mudstone of Unazawa Unit around the adit. There are a thick sandstone bed and a thin (approximately 10 m) chert block near the deposit. The deposit is in the thin mudstone bed at the boundary between sandstone and chert. Manganese deposits in Kanto moutains are usualy chert-hosted, but this is very unique mudstone-hosted deposit.
Reported Minerals
- Caryopilite
- Rhodochrosite
- Baryte?
- Hausmannite
- Sussexite
Mineral Assemblages
- Caryopilite - Rhodochrosite - Quartz
- Hausmannite - Rhodochrosite - Sussexite
- Caryopilite - Rhodochrosite - Baryte?
Localities
- Shintani Mine (Mudstone-hosted, Chichibu belt)
Related Occurrences
- Bedded Mn (Diagenesis)
- Bedded Mn (Low-T zeolite facies)
- Bedded Mn (High-T zeolite facies)
- Bedded Mn (Prehnite-Pumpellyite facies)
- Bedded Mn (Pumpellyite-Actinolite facies)
- Bedded Mn (Greenschist facies)
- Bedded Mn (Epidote-Amphibolite facies)
- Bedded Mn (Amphibolite facies)
- Bedded Mn (Albite-Epidote-hornfels facies)
- Bedded Mn (Hornblende-hornfels facies)
- Bedded Mn (Pyroxene-hornfels facies)