Vote for your favorite mineral in #MinCup26! - Hafnon vs. Putnisite
It's a pair of tiny minerals of unusual chemistry as orange Hafnon battles with purple Putnisite.
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Biotite from
Fort Knox Gold Mine, Fairbanks North Star Borough, Alaska, USA


Locality type:Mine
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 Fort Knox Gold Mine, Fairbanks North Star Borough, Alaska, USA
Data Identifiers
Mindat Occurrence Record ID:636891
Long-form Identifier:1:3:636891:3
GUID (UUID V4):0
Nearest other occurrences of Biotite
8.6km (5.4 miles) ⓘDolphin Prospect, Fairbanks Mining District, Fairbanks North Star Borough, Alaska, USA
8.7km (5.4 miles) ⓘLundgren-Rowley Prospect, Fairbanks Mining District, Fairbanks North Star Borough, Alaska, USA
36.6km (22.8 miles) ⓘRhyolite Prospect, Fairbanks Mining District, Fairbanks North Star Borough, Alaska, USA
60.4km (37.5 miles) ⓘChena Hot Springs (yugawaralite locality), Tors Campground Trail, Chena River, Fairbanks North Star Borough, Alaska, USA
82.9km (51.5 miles) ⓘTable Mountain Prospect, Circle Mining District, Yukon-Koyukuk Census Area, Alaska, USA
References
Econ Geol (1991) 86:402-405
 
and/or  
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