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
Valdarcas Mine, Covas, Vila Nova de Cerveira, Viana do Castelo, 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 Valdarcas Mine, Covas, Vila Nova de Cerveira, Viana do Castelo, Portugal
Data Identifiers
Mindat Occurrence Record ID:219312
Long-form Identifier:1:3:219312:0
GUID (UUID V4):0
Nearest other occurrences of Biotite
0.9km (0.6 miles) ⓘAplito-pegmatitic area, Covas, Vila Nova de Cerveira, Viana do Castelo, Portugal
11.1km (6.9 miles) ⓘCabanas Mine, Arcozelo, Ponte de Lima, Viana do Castelo, Portugal
33.5km (20.8 miles) ⓘMata da Galinheira Mine, Vila Chã (São João Baptista e Santiago), Ponte da Barca, Viana do Castelo, Portugal
33.5km (20.8 miles) ⓘMonte do Castelo da Pena Mine, Vila Chã (São João Baptista e Santiago), Ponte da Barca, Viana do Castelo, Portugal
34.6km (21.5 miles) ⓘPorriño quarries, Porriño, Pontevedra, Galicia, Spain
38.5km (23.9 miles) ⓘCillarga Quarry, Ponteareas, Pontevedra, Galicia, Spain
44.9km (27.9 miles) ⓘA Franqueira, A Cañiza, Pontevedra, Galicia, Spain
47.7km (29.7 miles) ⓘMount Ermelo, Moaña, Pontevedra, Galicia, Spain
54.4km (33.8 miles) ⓘBorrageiro Mine, Cabril, Montalegre, Vila Real, Portugal
64.8km (40.3 miles) ⓘBorralha Mines, Salto, Montalegre, Vila Real, Portugal
References
 
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