Vote for your favorite mineral in #MinCup26! - Quartz vs. Asagiite
It's a classic vs a newbie as the most common named mineral in the crust Quartz is up against an exceedingly-rare sea foam-green mineral discovered just a few years ago Asagiite.
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Biotite from
Kensington mine, Berners Bay Mining District, Juneau, 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 Kensington mine, Berners Bay Mining District, Juneau, Alaska, USA
Data Identifiers
Mindat Occurrence Record ID:567742
Long-form Identifier:1:3:567742:9
GUID (UUID V4):0
Nearest other occurrences of Biotite
59.8km (37.2 miles) ⓘNunatak Prospect (Muir Inlet), Hoonah-Angoon Census Area, Alaska, USA
68.1km (42.3 miles) ⓘLaverdiere Prospects, Hoboe Creek, Atlin Lake Area, Atlin Mining Division, British Columbia, Canada
79.7km (49.5 miles) ⓘReady Bullion mine, Treadwell ore deposits (Treadwell Mine; Treadwell Glory Hole), Douglas Island, Juneau, Alaska, USA
95.9km (59.6 miles) ⓘEricksen-Ashby deposit, Atlin Mining Division, British Columbia, Canada
References
Econ Geol (1995) 90:343-368
 
and/or  
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