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
A Franqueira, A Cañiza, Pontevedra, Galicia, Spain


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 A Franqueira, A Cañiza, Pontevedra, Galicia, Spain
Data Identifiers
Mindat Occurrence Record ID:788659
Long-form Identifier:1:3:788659:1
GUID (UUID V4):0
Nearest other occurrences of Biotite
15.7km (9.7 miles) ⓘCillarga Quarry, Ponteareas, Pontevedra, Galicia, Spain
17.9km (11.2 miles) ⓘPorriño quarries, Porriño, Pontevedra, Galicia, Spain
34.9km (21.7 miles) ⓘMount Ermelo, Moaña, Pontevedra, Galicia, Spain
43.6km (27.1 miles) ⓘPanceiros pegmatite, Campo Lameiro, Pontevedra, Galicia, Spain
44.9km (27.9 miles) ⓘMata da Galinheira Mine, Vila Chã (São João Baptista e Santiago), Ponte da Barca, Viana do Castelo, Portugal
44.9km (27.9 miles) ⓘValdarcas Mine, Covas, Vila Nova de Cerveira, Viana do Castelo, Portugal
45.5km (28.3 miles) ⓘMonte do Castelo da Pena Mine, Vila Chã (São João Baptista e Santiago), Ponte da Barca, Viana do Castelo, Portugal
45.8km (28.5 miles) ⓘAplito-pegmatitic area, Covas, Vila Nova de Cerveira, Viana do Castelo, Portugal
46.0km (28.6 miles) ⓘCabanas Mine, Arcozelo, Ponte de Lima, Viana do Castelo, Portugal
47.4km (29.4 miles) ⓘFontao mines, Silleda, Pontevedra, Galicia, Spain
References
Martin-Izard, A., Paniagua, A., Moreiras, D., Acevedo, R.D., and Marcos-Pascual, C. (1995) Metasomatism at a granitic pegmatite - dunite contact in Galicia: the Franqueira occurrence of chrysoberyl (alexandrite), emerald, and phenakite. The Canadian Mineralogist: 33: 775-792.
 
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