Marsturite
Shiromaru, Okutama city, Nishi-Tama county, Tokyo, Japan
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Width: 5mm. A crystal of marsturite. The yellowish-brown part is marsturite. It looks exhibiting cleavage. The surrounding massive white parts are albite or celsian.
Recovered from an albite or celsian vein in a chert-hosted bedded manganese deposit subjected to Zeolite facies metamorphism.
The first marsturite from Japan was reported from this location in 1990.
Other localities
- Shiromaru Mine (Bedded Mn, Massive)
- Tsurumaki Mine (Bedded Mn, Massive)