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Biotite from
Macedo de Cavaleiros Volcanic area, Bornes, Macedo de Cavaleiros, Bragança, Portugal


Locality type:Volcanic Complex
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 Macedo de Cavaleiros Volcanic area, Bornes, Macedo de Cavaleiros, Bragança, Portugal
Data Identifiers
Mindat Occurrence Record ID:1408575
Long-form Identifier:1:3:1408575:2
GUID (UUID V4):0
Nearest other occurrences of Biotite
23.7km (14.7 miles) ⓘMurçós Mines, Murçós, Macedo de Cavaleiros, Bragança, Portugal
29.1km (18.1 miles) ⓘErvedosa Mine (Tuela Mine), Ervedosa, Vinhais, Bragança, Portugal
34.7km (21.6 miles) ⓘTrigueiriça Mines, Rebordelo, Vinhais, Bragança, Portugal
41.6km (25.9 miles) ⓘAlijó spodumene pegmatite, São Mamede de Ribatua, Alijó, Vila Real, Portugal
47.2km (29.3 miles) ⓘLatedo, Trabazos, Zamora, Castile and Leon, Spain
48.3km (30.0 miles) ⓘVillarino trás la Sierra, Trabazos, Zamora, Castile and Leon, Spain
49.0km (30.4 miles) ⓘNumão prospect, Numão, Vila Nova de Foz Côa, Guarda, Portugal
49.4km (30.7 miles) ⓘSeixigal (Pereira de Selão), Vilas Boas, Vidago, Chaves, Vila Real, Portugal
50.6km (31.4 miles) ⓘSan Mamed, Rábano de Aliste, Zamora, Castile and Leon, Spain
54.2km (33.7 miles) ⓘBarruecopardo Mine, Barruecopardo, Salamanca, Castile and Leon, Spain
References
Ribeiro, M. L. (1987). Petrogenesis of early paleozoic peralkaline rhyolites from the Macedo de Cavaleiros region (NE Portugal). Geologische Rundschau, 76(1), 147-168.
 
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