Braunite
Tabi, Numazu city, Shizuoka pref., Japan
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Field of view: 5 mm. Granular braunite. The black grains are pseudo-octahedral penetration twins of braunite. Braunite distributes as a network in the pale brown tuff.
Recovered from a Fe-Mn deposit by a low-temperature hydrothermal activity associated with andesitic pyroclastic rocks.
Braunite from this location was described in 1970.
Other localities
- Iwaisawa Mine (Bedded Mn, Massive)
- Tone Mine (Bedded Mn, Pseudo-octahedral)
- Tabi (Hydrothermal, Pseudo-octahedral)