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
Assunção Mine, Aldeia Nova, Ferreira de Aves, Sátão, Viseu, Portugal


02523990017362447142654.jpg
Siderophyllite

Assunção Mine, Aldeia Nova, Ferreira de Aves, Sátão, Viseu, Portugal
08195020017362447916646.jpg
Siderophyllite

Assunção Mine, Aldeia Nova, Ferreira de Aves, Sátão, Viseu, Portugal
01378210017417214416290.jpg
Siderophyllite

Assunção Mine, Aldeia Nova, Ferreira de Aves, Sátão, Viseu, Portugal
07308330017362449571018.jpg
Siderophyllite

Assunção Mine, Aldeia Nova, Ferreira de Aves, Sátão, Viseu, Portugal
04444720017362446349959.jpg
Siderophyllite

Assunção Mine, Aldeia Nova, Ferreira de Aves, Sátão, Viseu, Portugal
09204750017362447756034.jpg
Siderophyllite

Assunção Mine, Aldeia Nova, Ferreira de Aves, Sátão, Viseu, Portugal
03452970017417214359391.jpg
Siderophyllite

Assunção Mine, Aldeia Nova, Ferreira de Aves, Sátão, Viseu, Portugal
07983200017362449471696.jpg
Siderophyllite

Assunção Mine, Aldeia Nova, Ferreira de Aves, Sátão, Viseu, Portugal
00123820017362447934600.jpg
Siderophyllite

Assunção Mine, Aldeia Nova, Ferreira de Aves, Sátão, Viseu, Portugal
02221370017362447937290.jpg
Siderophyllite

Assunção Mine, Aldeia Nova, Ferreira de Aves, Sátão, Viseu, Portugal
07891550017418775111627.jpg
Siderophyllite

Assunção Mine, Aldeia Nova, Ferreira de Aves, Sátão, Viseu, Portugal
07139460017362536002500.jpg
Siderophyllite

Assunção Mine, Aldeia Nova, Ferreira de Aves, Sátão, Viseu, 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
Associated Minerals Based on Photo Data:
Torbernite1
Data
Mineral Data:Click here to view Biotite data
Locality Data:Click here to view Assunção Mine, Aldeia Nova, Ferreira de Aves, Sátão, Viseu, Portugal
Data Identifiers
Mindat Occurrence Record ID:220197
Long-form Identifier:1:3:220197:9
GUID (UUID V4):0
Nearest other occurrences of Biotite
3.3km (2.1 miles) ⓘVigia Mine, U.F. Aguiar da Beira e Coruche, Aguiar da Beira, Guarda, Portugal
5.6km (3.5 miles) ⓘRatoeira quarry, U.F. Sequeiros e Gradiz, Aguiar da Beira, Guarda, Portugal
6.1km (3.8 miles) ⓘFonte Limeira quarry, U.F Romãs Decermilo e Vila Longa, Sátão, Viseu, Portugal
6.3km (3.9 miles) ⓘRatoeira No. 1 quarry, U.F. Sequeiros e Gradiz, Aguiar da Beira, Guarda, Portugal
12.2km (7.6 miles) ⓘVenturinha, Sezures, Penalva do Castelo, Viseu, Portugal
20.9km (13.0 miles) ⓘVila Seca Mine, Vila Seca, Tavares (Chãs; Várzea e Travanca), Mangualde, Viseu, Portugal
25.2km (15.6 miles) ⓘRegada, Cubos-Mesquitela-Mangualde area, Mangualde (Mesquitela e Cunha Alta), Mangualde, Viseu, Portugal
28.0km (17.4 miles) ⓘRochel, Cubos-Mesquitela-Mangualde area, Mangualde (Mesquitela e Cunha Alta), Mangualde, Viseu, Portugal
28.1km (17.5 miles) ⓘChão do Castanheiro, Cubos-Mesquitela-Mangualde area, Mangualde (Mesquitela e Cunha Alta), Mangualde, Viseu, Portugal
28.5km (17.7 miles) ⓘCubos-Mesquitela-Mangualde area, Mangualde (Mesquitela e Cunha Alta), Mangualde, Viseu, Portugal
References
 
and/or  
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