Augite
Horaku creek
Toyohashi, Shimo-Suwa city, Suwa county, Nagano pref., Japan
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Bottom crystal: 5 mm long. Dispatched augite phenocrysts of andesite. Augite specimens are radial penetration twins.
Recovered from a basalt lava erupted at the early stage of a continental volcano activity. Formed in the early Pleistocene (1.5 Ma).
Augite from this location was described in 1979.
Other localities
- Mount Hijiri (Andesite, Floater)
- Akima river (Andesite, Floater)
- Yaga (Andesite dike)
- Shishi-Iwa (Tuff breccia, Floater)
- Horaku creek (Basalt, Floater)