Iwaisawa Mine
Kitagawa, Hanno city, Saitama pref., Japan
Occurrence
Pumpellyite-Actinolite facies bedded manganese deposit
Chert-hosted bedded manganese deposit in a chert block of Kamiyoshida unit, a member of accretionary complexes of Northern Chichibu Belt.
Outcrop at the entrance of an adit. The adit is opened on the outcrop of brown bedded chert of Kamiyoshida unit. Its surface turns black by oxidation of manganese in the deposit, which is the typical feature of the manganese deposit.
Reported Minerals
- Cinnabar
- Pyrite
- Hematite
- Rhodochrosite
- Manganite
- Calcite
- Braunite
- Piemontite
- Caryopilite
- Bannisterite
- Taneyamalite
- Pyrolusite?
Mineral Assemblages
- Braunite - Quartz - Hematite - Piemontite
- Quartz - Hematite - Caryopilite - Rhodochrosite - Pyrite
- Quartz - Caryopilite - Cinnabar
- Caryopilite - Quartz - Rhodochrosite - Taneyamalite
- Caryopilite - Quartz - Rhodochrosite - Bannisterite
Localities
- Omiya Mine (Hausmannite)
- Iwaisawa Mine (Braunite)
- Hinozawa Mine (Rhodochrosite)
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)