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
Villafranca de la Sierra quarry, Villafranca de la Sierra, Ávila, Castile and Leon, Spain


Locality type:Quarry
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 Villafranca de la Sierra quarry, Villafranca de la Sierra, Ávila, Castile and Leon, Spain
Data Identifiers
Mindat Occurrence Record ID:1616882
Long-form Identifier:1:3:1616882:8
GUID (UUID V4):0
Nearest other occurrences of Biotite
47.1km (29.2 miles) ⓘLos Santos W deposit, Los Santos, Salamanca, Castile and Leon, Spain
76.7km (47.7 miles) ⓘGolpejas Mining Group, Golpejas, Salamanca, Castile and Leon, Spain
77.9km (48.4 miles) ⓘMimosa Mine, Aldehuela de la Bóveda, Salamanca, Castile and Leon, Spain
89.1km (55.3 miles) ⓘVillar del Pedroso granite, Villar del Pedroso, Cáceres, Extremadura, Spain
91.9km (57.1 miles) ⓘOtero de Herreros area, Segovia, Castile and Leon, Spain
References
Orejana, David, Villaseca, Carlos, Losantos, Emma, Andonaegui, Pilar (2024) Petrology and Geochemistry of Highly Differentiated Tholeiitic Magmas: Granophyres in the Messejana–Plasencia Great Dyke (Central Iberia) Minerals, 14 (3) doi:10.3390/min14030316
 
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