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Biotite from
Tin Mountain Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA


Locality type:Mine
Classification
Species:'Biotite' (not an IMA approved species)
Formula:K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Biotite data
Locality Data:Click here to view Tin Mountain Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
Data Identifiers
Mindat Occurrence Record ID:137486
Long-form Identifier:1:3:137486:5
GUID (UUID V4):0
Nearest other occurrences of Biotite
1.1km (0.7 miles) ⓘWright Mica Lode, Custer Mining District, Custer County, South Dakota, USA
2.8km (1.7 miles) ⓘRainbow No. 4 Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
3.5km (2.2 miles) ⓘBig Tom Mine (Kem Lode), Custer Mining District, Custer County, South Dakota, USA
4.2km (2.6 miles) ⓘHelen Beryl Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
5.4km (3.3 miles) ⓘTip Top Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
6.5km (4.1 miles) ⓘDorothy V Prospect (Van), Custer Mining District, Custer County, South Dakota, USA
8.5km (5.3 miles) ⓘBuster lode (Buster Dike Mica Mine), Custer, Custer Mining District, Custer County, South Dakota, USA
8.7km (5.4 miles) ⓘLucky Star Prospect, Custer Mining District, Custer County, South Dakota, USA
8.8km (5.5 miles) ⓘSilver Dollar Mine, Custer Mining District, Custer County, South Dakota, USA
8.8km (5.5 miles) ⓘRay Prospect (Ray Mica Prospect), Custer Mining District, Custer County, South Dakota, USA
References
Rocks & Minerals: 60: 117-118.
Staatz, M. H.
Norton, J. J.
Page, Lincoln R., Stocking, Hobart E., Smith, Harriet B. (1956) Contributions to the geology of uranium and thorium by the United States Geological Survey and Atomic Energy Commission for the United Nations International Conference on Peaceful Uses of Atomic Energy, Geneva, Switzerland, 1955. Professional Paper 300. US Geological Survey doi:10.3133/pp300
Wilmarth, V. R. (1963) Exploration for beryllium at the Helen Beryl, Elkhorn, and Tin Mountain pegmatites, Custer County, South Dakota. USGS Prof. Paper 297C.
 
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