Opal
Konaka, Azuma village, Midori city, Gunma pref., Japan
Field of view: 1 mm. Opal associated with rhodonite. The massive white to transparent parts are opal. The red- and blue-based rainbow color is the play of color of noble opal. The surrounding red host is rhodonite. The red tabular crystals in opal is rhodonite.
Recovered from a chert-hosted bedded manganese deposit subjected to Hornblende-hornfels facies contact metamorphism.
Other localities
- Hagidaira Mine (Bedded Mn, Noble Opal)
- Hosaka (Rhyolite, Nodule)
- Sukayu hot spring (Hot spring, Massive)
- Opal Quest Mine (Shale, replacing Bivalvia)
- Old Timers Mine (Shale, replacing Bivalvia)