Vote for your favorite mineral in #MinCup26! - Cuprite vs. Halite
While externally similar shapes, these two minerals are very different inside.
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Biotite from
New Cornelia Mine, Ajo, Little Ajo Mountains, Ajo Mining District, Pima County, Arizona, 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
Comments:Rock forming mineral. Occurs in the Cardigan gneiss, Concentrator volcanics, and Cornelia quartz monzonite. A little broadleaved material associated with pegmatized part of the Cornelia quartz monzonite in the orebody.
Confirmation
Validity:Believed Valid
Associated Minerals:
Associates:Anhydrite
Data
Mineral Data:Click here to view Biotite data
Locality Data:Click here to view New Cornelia Mine, Ajo, Little Ajo Mountains, Ajo Mining District, Pima County, Arizona, USA
Data Identifiers
Mindat Occurrence Record ID:46652
Long-form Identifier:1:3:46652:5
GUID (UUID V4):0
Nearest other occurrences of Biotite
92.3km (57.3 miles) ⓘLakeshore Mine, North Komelik area, Casa Grande Mining District, Pinal County, Arizona, USA
References
Thomas, William J., Gibbs, Ronald B. (1983) Famous Mineral Localities: The New Cornelia Mine, Ajo, Arizona. The Mineralogical Record, 14 (5) 283-298
 
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