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
Margerie Glacier prospect (Margarie Glacier prospect; Porcupine prospect), Glacier Bay Mining District, Juneau Mining District, Alaska, USA


Locality type:Prospect
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 Margerie Glacier prospect (Margarie Glacier prospect; Porcupine prospect), Glacier Bay Mining District, Juneau Mining District, Alaska, USA
Data Identifiers
Mindat Occurrence Record ID:629341
Long-form Identifier:1:3:629341:3
GUID (UUID V4):0
Nearest other occurrences of Biotite
56.2km (34.9 miles) ⓘNunatak Prospect (Muir Inlet), Hoonah-Angoon Census Area, Alaska, USA
67.5km (42.0 miles) ⓘMaid of Erin Mine, Rainy Hollow District, Atlin Mining Division, British Columbia, Canada
80.3km (49.9 miles) ⓘWindy Craggy deposit, Atlin Mining Division, British Columbia, Canada
References
Singer, D.A., Berger, V.I., Moring, B.C. (2008) Porphyry copper deposits of the world: Database and grade and tonnage models, 2008. Open-File Report 2008-1155
 
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