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
Numão prospect, Numão, Vila Nova de Foz Côa, Guarda, Portugal


Locality type:Prospect
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 Numão prospect, Numão, Vila Nova de Foz Côa, Guarda, Portugal
Data Identifiers
Mindat Occurrence Record ID:1497675
Long-form Identifier:1:3:1497675:5
GUID (UUID V4):0
Nearest other occurrences of Biotite
28.5km (17.7 miles) ⓘSão Pedro das Águias Mine, U.F Távora e Pereiro, Tabuaço, Viseu, Portugal
30.1km (18.7 miles) ⓘAlijó spodumene pegmatite, São Mamede de Ribatua, Alijó, Vila Real, Portugal
39.0km (24.3 miles) ⓘRatoeira No. 1 quarry, U.F. Sequeiros e Gradiz, Aguiar da Beira, Guarda, Portugal
39.7km (24.7 miles) ⓘPortugal 1 & 2 quarries, Malpartida, Malpartida e Vale de Coelha, Almeida, Guarda, Portugal
39.8km (24.7 miles) ⓘRatoeira quarry, U.F. Sequeiros e Gradiz, Aguiar da Beira, Guarda, Portugal
42.6km (26.5 miles) ⓘVigia Mine, U.F. Aguiar da Beira e Coruche, Aguiar da Beira, Guarda, Portugal
43.1km (26.8 miles) ⓘBarruecopardo Mine, Barruecopardo, Salamanca, Castile and Leon, Spain
45.4km (28.2 miles) ⓘAssunção Mine, Aldeia Nova, Ferreira de Aves, Sátão, Viseu, Portugal
48.4km (30.1 miles) ⓘFonte Limeira quarry, U.F Romãs Decermilo e Vila Longa, Sátão, Viseu, Portugal
49.0km (30.4 miles) ⓘMacedo de Cavaleiros Volcanic area, Bornes, Macedo de Cavaleiros, Bragança, Portugal
References
Leal, S.; Lima, A.; Morris, J.; Pedro, M.; Noronha, F. (2022) Numão gold deposit in the Iberian Variscan belt, Northern Portugal: Ore features and mineralization controls. A gold deposit in a W-Sn metallogenic province. Ore Geology Reviews, 144. 104815 doi:10.1016/j.oregeorev.2022.104815
 
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