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Biotite from
Elkhorn Mine (Tinsley Mine), Custer, 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 Elkhorn Mine (Tinsley Mine), Custer, Custer Mining District, Custer County, South Dakota, USA
Data Identifiers
Mindat Occurrence Record ID:211324
Long-form Identifier:1:3:211324:1
GUID (UUID V4):0
Nearest other occurrences of Biotite
0.7km (0.4 miles) ⓘMica King Mine (Lost Bonanza; Cook Mine), Custer Mining District, Custer County, South Dakota, USA
5.3km (3.3 miles) ⓘHofert Arcade (Victory No. 1 Prospect), Custer Mining District, Custer County, South Dakota, USA
6.7km (4.1 miles) ⓘBurgess Mica Prospect, Custer Mining District, Custer County, South Dakota, USA
6.8km (4.2 miles) ⓘBig Horn Lode Prospect, Custer Mining District, Custer County, South Dakota, USA
7.4km (4.6 miles) ⓘSurprise Mica Mine, Custer Mining District, Custer County, South Dakota, USA
7.7km (4.8 miles) ⓘLucky Star Prospect, Custer Mining District, Custer County, South Dakota, USA
7.9km (4.9 miles) ⓘKnowles lode claim, Custer, Custer Mining District, Custer County, South Dakota, USA
8.0km (5.0 miles) ⓘWhite Bear Mine (Gamber Mine), Custer, Custer Mining District, Custer County, South Dakota, USA
8.1km (5.0 miles) ⓘSunshine Mica Prospect, Custer Mining District, Custer County, South Dakota, USA
8.2km (5.1 miles) ⓘBuster lode (Buster Dike Mica Mine), Custer, Custer Mining District, Custer County, South Dakota, USA
References
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.
Smith, Arthur E., Fritzsch, Eric (2000) SOUTH DAKOTA. Rocks & Minerals, 75 (3) 156-169 doi:10.1080/00357520009605635
 
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