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Microcline from
Helen Beryl Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA


09531930017369571785548.jpg
Microcline, etc.

Helen Beryl Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
09531930017369571785548.jpg
Microcline, etc.

Helen Beryl Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
08107470017369571795416.jpg
Microcline, etc.

Helen Beryl Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
Locality type:Mine
Classification
Species:Microcline
Formula:K(AlSi3O8)
Comments:Occurs in pegmatite.
Confirmation
Validity:Believed Valid
Associated Minerals Based on Photo Data:
Quartz8
Muscovite6
Beryl3
Fluorapatite1
Schorl1
Albite1
Data
Mineral Data:Click here to view Microcline data
Locality Data:Click here to view Helen Beryl Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
Data Identifiers
Mindat Occurrence Record ID:68282
Long-form Identifier:1:3:68282:2
GUID (UUID V4):0
Nearest other occurrences of Microcline
1.4km (0.9 miles) ⓘNew York Mine (Westinghouse No. 1 Mine), Custer, Custer Mining District, Custer County, South Dakota, USA
1.9km (1.2 miles) ⓘRainbow No. 4 Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
2.2km (1.4 miles) ⓘTip Top Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
2.2km (1.4 miles) ⓘTom Carroll Claim, Custer Mining District, Custer County, South Dakota, USA
3.2km (2.0 miles) ⓘDubuque and Royal Flush Claims (Gayle Lode), Custer Mining District, Custer County, South Dakota, USA
3.3km (2.0 miles) ⓘKeystone Lode Occurrence, Custer Mining District, Custer County, South Dakota, USA
3.7km (2.3 miles) ⓘMoon Lode Prospect, Custer Mining District, Custer County, South Dakota, USA
4.2km (2.6 miles) ⓘHighview Prospect, Custer Mining District, Custer County, South Dakota, USA
4.2km (2.6 miles) ⓘWright Mica Lode, Custer Mining District, Custer County, South Dakota, USA
4.2km (2.6 miles) ⓘTin Mountain Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
References
Rocks & Minerals: 60: 117.
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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