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Biotite from
Shonkin Sag laccolith, Highwood Mountains, Chouteau County, Montana, USA


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 Shonkin Sag laccolith, Highwood Mountains, Chouteau County, Montana, USA
Data Identifiers
Mindat Occurrence Record ID:784277
Long-form Identifier:1:3:784277:1
GUID (UUID V4):0
Nearest other occurrences of Biotite
22.3km (13.9 miles) ⓘHighwood Mountains, Chouteau County, Montana, USA
81.0km (50.4 miles) ⓘVermiculite prospect No. 6, Big Sandy Creek, Bearpaw Mountains, Hill County, Montana, USA
81.1km (50.4 miles) ⓘUnnamed Uranium - Zinc - Niobium (Columbium) - Copper - Lead - Zirconium - Titanium - Metal Occurrence (Vermiculite Prospect; MRDS - 10019371), Hill County, Montana, USA
81.6km (50.7 miles) ⓘRocky Boy Stock Occurrence, Hill County, Montana, USA
References
A differentiated alkaline intrusion, Highwood Mountains, Montana", Rocky Mountain Section of the Geological Society of America, Stanley S. Beus
W. P. Nash, Lawrence M. Monson, (1987) "Shonkin Sag laccolith
Gobla, Michael J. (2012) Montana Mineral Locality Index. Rocks & Minerals, 87 (3) 208-240 doi:10.1080/00357529.2012.676825
 
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