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Ikenofukuro

Sakai, Fujimi city, Suwa county, Nagano pref., Japan

Occurrence

Andesite

Phenocryst of andesite in Pleistocene Shinanosakai Lava. Some lavas of Yatsugatake volcano produce hornblende mega-crystals.

Ikebukuro

Outcrop of andesite of Shinanosakai Lava. The black crystals are hornblende phenocrysts. The fine white crystals are anorthite phenocrysts. Local people have called dispatched hornblende as "Roppo-ishi", hexagonal stone in Japanese, for more than 100 years.

Reported Minerals

Mineral Assemblages

  • Andesite (Host) - Hornblende

Localities

Related Occurrences

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