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


Locality type:Mine
Classification
Species:Montmorillonite
Formula:(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Montmorillonite 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:137490
Long-form Identifier:1:3:137490:2
GUID (UUID V4):0
Nearest other occurrences of Montmorillonite
27.4km (17.1 miles) ⓘHugo Mine, Keystone, Keystone Mining District, Pennington County, South Dakota, USA
28.4km (17.6 miles) ⓘEtta Mine, Keystone, Keystone Mining District, Pennington County, South Dakota, USA
80.7km (50.2 miles) ⓘRefinite Corp Bentonite Pit, Ardmore, Fall River County, South Dakota, USA
81.1km (50.4 miles) ⓘArdmore, Fall River County, South Dakota, USA
References
Rocks & Minerals: 60: 117-118.
 
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