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Opal from
Barker-Ferguson Mine, Keystone, Keystone Mining District, Pennington County, South Dakota, USA


Locality type:Mine
Classification
Species:Opal
Formula:SiO2 · nH2O
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Opal data
Locality Data:Click here to view Barker-Ferguson Mine, Keystone, Keystone Mining District, Pennington County, South Dakota, USA
Data Identifiers
Mindat Occurrence Record ID:212303
Long-form Identifier:1:3:212303:5
GUID (UUID V4):0
Nearest other occurrences of Opal
0.8km (0.5 miles) ⓘWood Tin mine, Harney City, Pennington County, South Dakota, USA
1.9km (1.2 miles) ⓘKing Lithia Mine, Greyhound Gulch, Keystone, Keystone Mining District, Pennington County, South Dakota, USA
4.1km (2.5 miles) ⓘEtta Mine, Keystone, Keystone Mining District, Pennington County, South Dakota, USA
4.3km (2.7 miles) ⓘPeerless Mine, Keystone, Keystone Mining District, Pennington County, South Dakota, USA
14.5km (9.0 miles) ⓘNovember Mine, The Needles, Custer State Park, Custer County, South Dakota, USA
32.3km (20.1 miles) ⓘHelen Beryl Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
64.2km (39.9 miles) ⓘWharf Mine, Bald Mountain Mining District (Portland Mining District), Lawrence County, South Dakota, USA
64.4km (40.0 miles) ⓘDavier Mine, Annie Creek, Bald Mountain Mining District (Portland Mining District), Lawrence County, South Dakota, USA
References
Smith, Arthur E., Fritzsch, Eric (2000) SOUTH DAKOTA. Rocks & Minerals, 75 (3) 156-169 doi:10.1080/00357520009605635
 
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