Goethite
Otaki, Chichibu city, Saitama pref., Japan
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Field of view: 40 mm. A group of goethite. The reniform black group is goethite. The white host is quartz.
Recovered from an open space of a quartz vein of a meteoric oxidation zone of a moderately low-temperature hydrothermal deposit combined with skarn formed by contact metamorphism of I-type (magnetite-series) quartz diorite.
Goethite from this location was described in 1982.
Other localities
- Kobushi Mine (Pneumatolytlic Skarn, replacing Pyrite)
- Chichibu Mine (Hydrothermal Skarn, Reniform)
- Nakatatsu Mine (Hydrothermal Skarn, Reniform)
- Mikawa Mine (Hydrothermal, Acicular)
- Gunma Mine (Bog Iron, replacing Plants)
- Sukayu hot spring (Bog Iron)
- Mount Takeshi (Tuff, replacing Pyrite)