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
Monte de Entre-Portelas Mine (S. João Mine; Adoria Mine), Cerva e Limões, Ribeira de Pena, Vila Real, Portugal


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 Monte de Entre-Portelas Mine (S. João Mine; Adoria Mine), Cerva e Limões, Ribeira de Pena, Vila Real, Portugal
Data Identifiers
Mindat Occurrence Record ID:221791
Long-form Identifier:1:3:221791:8
GUID (UUID V4):0
Nearest other occurrences of Biotite
12.4km (7.7 miles) ⓘLamas de Olo pluton, Vila Marim, Vila Real, Vila Real, Portugal
25.1km (15.6 miles) ⓘBorralha Mines, Salto, Montalegre, Vila Real, Portugal
34.9km (21.7 miles) ⓘSeixigal (Pereira de Selão), Vilas Boas, Vidago, Chaves, Vila Real, Portugal
38.7km (24.0 miles) ⓘLimarinho deposit, Ardãos e Bobadela, Boticas, Vila Real, Portugal
40.2km (25.0 miles) ⓘBorrageiro Mine, Cabril, Montalegre, Vila Real, Portugal
42.5km (26.4 miles) ⓘAlijó spodumene pegmatite, São Mamede de Ribatua, Alijó, Vila Real, Portugal
49.2km (30.6 miles) ⓘSão Pedro das Águias Mine, U.F Távora e Pereiro, Tabuaço, Viseu, Portugal
53.3km (33.1 miles) ⓘMonte do Castelo da Pena Mine, Vila Chã (São João Baptista e Santiago), Ponte da Barca, Viana do Castelo, Portugal
53.5km (33.3 miles) ⓘMata da Galinheira Mine, Vila Chã (São João Baptista e Santiago), Ponte da Barca, Viana do Castelo, Portugal
66.1km (41.1 miles) ⓘTrigueiriça Mines, Rebordelo, Vinhais, Bragança, Portugal
References
 
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