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
Unnamed pegmatite, Rancajales, San Pedro Massif, Soto del Real, Community of Madrid, Spain


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 Unnamed pegmatite, Rancajales, San Pedro Massif, Soto del Real, Community of Madrid, Spain
Data Identifiers
Mindat Occurrence Record ID:843958
Long-form Identifier:1:3:843958:1
GUID (UUID V4):0
Nearest other occurrences of Biotite
9.4km (5.8 miles) ⓘArroyo de la Yedra, Manzanares el Real, Community of Madrid, Spain
39.4km (24.5 miles) ⓘLa Garita Stream, Horcajuelo de la Sierra, Community of Madrid, Spain
41.3km (25.7 miles) ⓘOtero de Herreros area, Segovia, Castile and Leon, Spain
73.5km (45.7 miles) ⓘSanta Cecilia Mine, Hiendelaencina, Guadalajara, Castile-La Mancha, Spain
87.3km (54.2 miles) ⓘAlpedroches andesite quarry, Alpedroches, Atienza, Guadalajara, Castile-La Mancha, Spain
References
Gonzalez del Tánago J. (1985) Las Pegmatitas Graníticas de San Pedro, Sistema Central Español. Bol. Soc. Española de Mineralogía, pp. 207-2017.
 
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