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
Ratoeira quarry, U.F. Sequeiros e Gradiz, Aguiar da Beira, Guarda, Portugal


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:Confirmed
Confirmation Methods:Visually Identified
Data
Mineral Data:Click here to view Biotite data
Locality Data:Click here to view Ratoeira quarry, U.F. Sequeiros e Gradiz, Aguiar da Beira, Guarda, Portugal
Data Identifiers
Mindat Occurrence Record ID:747112
Long-form Identifier:1:3:747112:4
GUID (UUID V4):0
Nearest other occurrences of Biotite
0.7km (0.5 miles) ⓘRatoeira No. 1 quarry, U.F. Sequeiros e Gradiz, Aguiar da Beira, Guarda, Portugal
3.4km (2.1 miles) ⓘVigia Mine, U.F. Aguiar da Beira e Coruche, Aguiar da Beira, Guarda, Portugal
5.6km (3.5 miles) ⓘAssunção Mine, Aldeia Nova, Ferreira de Aves, Sátão, Viseu, Portugal
10.1km (6.3 miles) ⓘFonte Limeira quarry, U.F Romãs Decermilo e Vila Longa, Sátão, Viseu, Portugal
16.6km (10.3 miles) ⓘVenturinha, Sezures, Penalva do Castelo, Viseu, Portugal
24.3km (15.1 miles) ⓘVila Seca Mine, Vila Seca, Tavares (Chãs; Várzea e Travanca), Mangualde, Viseu, Portugal
26.4km (16.4 miles) ⓘSão Pedro das Águias Mine, U.F Távora e Pereiro, Tabuaço, Viseu, Portugal
30.3km (18.8 miles) ⓘRegada, Cubos-Mesquitela-Mangualde area, Mangualde (Mesquitela e Cunha Alta), Mangualde, Viseu, Portugal
32.9km (20.4 miles) ⓘRochel, Cubos-Mesquitela-Mangualde area, Mangualde (Mesquitela e Cunha Alta), Mangualde, Viseu, Portugal
33.0km (20.5 miles) ⓘChão do Castanheiro, Cubos-Mesquitela-Mangualde area, Mangualde (Mesquitela e Cunha Alta), Mangualde, Viseu, Portugal
References
Alves, Pedro (n.d.) Personal communication.
 
and/or  
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