Ilvaite
Horado-Komi, Seki city, Gifu pref., Japan
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Field of view: 40 mm. Ilvaite associated with grossular. The black parts are groups of ilvaite grains. The surrounding white host is quartz. The group of grayish-green grains at the right is grossular.
Recovered from a moderate-temperature hydrothermal deposit combined with skarn formed by contact metamorphism of I-type (magnetite-series) granite associated with a caldera complex. Formed in the early Paleocene (65 Ma).
Ilvaite from this location was described in 1952.
Other localities
- Chichibu Mine (Hydrothermal Skarn, Prismatic)
- Horado Mine (Hydrothermal Skarn, Granular)
- Obira Mine (Pneumatolytic Skarn, Prismatic)
- Kamioka Mine (Pneumatolytic Skarn, Granular)