Mount Orihime
Ashikaga city, Tochigi pref., Japan
Occurrence
Large dendrite on a Permian Cisuralian (280 Ma) bedded chert block of the Early Jurassic (180 Ma) Omama Unit. The Omama Unit corresponds to the Funafuseyama Unit of the Tamba-Mino-Ashio accretionary complex. Ages of sedimentary rocks were determined by radiolarians.

Outcrop of bedded chert of the Omama Unit associated with dendritic lithiophorite. The grayish-white host is chert, and the bluish-black part is lithiophorite. Thin dendritic lithiophorite is not rare, and called as dendrite. However, this unusual specimen is more than 5mm. The source of manganese is thought to be the bedded manganese deposit near by.
Reported Minerals
- Lithiophorite
Mineral Assemblage
- Chert(Host) - Lithiophorite
Localities
- Shimo-jinya (Conglomerate, Lithiophorite)
- Mount Orihime (Chert, Lithiophorite)
- Masaka (Chert, Lithiophorite)
- Umoona Mine (Opal deposit)
- Old Timers Mine (Gypsum, Fibrous)
- Opal Quest Mine(Gypsum, Rosette)
- Moon plain (Gypsum, Tabular)
- Jweller's shop noodling area (Chalcedony)