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Montmorillonite from
Refinite Corp Bentonite Pit, Ardmore, Fall River County, South Dakota, USA


Locality type:Pit
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 Refinite Corp Bentonite Pit, Ardmore, Fall River County, South Dakota, USA
Data Identifiers
Mindat Occurrence Record ID:385666
Long-form Identifier:1:3:385666:6
GUID (UUID V4):0
Nearest other occurrences of Montmorillonite
0.4km (0.2 miles) ⓘArdmore, Fall River County, South Dakota, USA
80.7km (50.2 miles) ⓘTin Mountain Mine, Fourmile, Custer Mining District, Custer County, South Dakota, USA
96.3km (59.8 miles) ⓘHugo Mine, Keystone, Keystone Mining District, Pennington County, South Dakota, USA
97.4km (60.5 miles) ⓘEtta Mine, Keystone, Keystone Mining District, Pennington County, South Dakota, USA
References
Roberts, Willard Lincoln, Rapp, George Jr. (1965) Mineralogy of the Black Hills. Bulletin 18. South Dakota School of Mines and Technology
 
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