Quartz/Japan Twin
Kobushi Mine
Azusayama, Kawakami city, Minami-Saku county, Nagano pref., Japan
This locality is closed to collecting.
Source for silicon
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Left twin: 5 mm. Japan twins of quartz. The left twin is perched on a small prism of quartz. The right crystal is a part of a broken twin.
Recovered from skarn formed by contact metamorphism of S-type (Ilmenite-series) diorite.
Quartz from this location was described in 1953.
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Lower right crystal: 10 mm. Transparent to white quartz crystals.
Other localities
- Kobushi Mine (Skarn, Japanese twin)
- Sanjyo Mine (Skarn, Japanese twin)
- Akatani Mine (Skarn, Green)
- Hirukawa (Pegmatite, Black)
- Otome Mine (Alpine Fissure)
- Takemori (Alpine Fissure, Phantom/Double pointed/Inclusions)
- Mount Ogawa (Alpine Fissure)
- Takaneyama Mine (Hydrothermal, Radial)
- Arakawa Mine (Hydrothermal)