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.
Log InRegister
Quick Links : The Mindat ManualThe Rock H. Currier Digital LibraryMindat Newsletter [Free Download]
Home PageAbout MindatThe Mindat ManualHistory of MindatCopyright StatusWho We AreContact UsAdvertise on Mindat
Donate to MindatCorporate SponsorshipSponsor a PageSponsored PagesMindat AdvertisersAdvertise on Mindat
Learning CenterWhat is a mineral?The most common minerals on earthInformation for EducatorsMindat ArticlesThe ElementsThe Rock H. Currier Digital LibraryGeologic TimeExplore Fossils
Minerals by PropertiesMinerals by ChemistryMineral Visual ExplorerAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
Mining CompaniesStatisticsUsersMineral MuseumsClubs & OrganizationsMineral Shows & EventsThe Mindat DirectoryDevice SettingsThe Mineral QuizTime Machine
Photo SearchPhoto GalleriesSearch by ColorPhoto Colour ExplorerNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day GalleryPhotography

Biotite from
Arreigada, Paços de Ferreira, Porto, Portugal


Locality type:Civil Parish
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 Arreigada, Paços de Ferreira, Porto, Portugal
Data Identifiers
Mindat Occurrence Record ID:223295
Long-form Identifier:1:3:223295:9
GUID (UUID V4):0
Nearest other occurrences of Biotite
43.6km (27.1 miles) ⓘFreita Mountain, Albergaria da Serra, Arouca, Aveiro, Portugal
45.1km (28.0 miles) ⓘCastanheira, Albergaria da Serra, Cabreiros e Albergaria da Serra, Arouca, Aveiro, Portugal
46.5km (28.9 miles) ⓘRegoufe Mines, Covelo de Paivó, Arouca, Aveiro, Portugal
51.4km (31.9 miles) ⓘLamas de Olo pluton, Vila Marim, Vila Real, Vila Real, Portugal
51.5km (32.0 miles) ⓘMonte de Entre-Portelas Mine (S. João Mine; Adoria Mine), Cerva e Limões, Ribeira de Pena, Vila Real, Portugal
57.4km (35.7 miles) ⓘBorralha Mines, Salto, Montalegre, Vila Real, Portugal
59.0km (36.7 miles) ⓘMonte do Castelo da Pena Mine, Vila Chã (São João Baptista e Santiago), Ponte da Barca, Viana do Castelo, Portugal
59.6km (37.0 miles) ⓘMata da Galinheira Mine, Vila Chã (São João Baptista e Santiago), Ponte da Barca, Viana do Castelo, Portugal
64.6km (40.1 miles) ⓘCabanas Mine, Arcozelo, Ponte de Lima, Viana do Castelo, Portugal
65.3km (40.6 miles) ⓘBorrageiro Mine, Cabril, Montalegre, Vila Real, Portugal
References
 
and/or  
Mindat.org® is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization. Mindat® and mindat.org® are registered trademarks of the Hudson Institute of Mineralogy.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2026, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters. Founded in 2000 by Jolyon Ralph and Ida Chau.
Content on this site may not be used to train, fine-tune, or otherwise develop artificial intelligence or machine learning models without prior written permission - see our Terms & Conditions.
To cite: Ralph, J., Von Bargen, D., Martynov, P., Zhang, J., Que, X., Prabhu, A., Morrison, S. M., Li, W., Chen, W., & Ma, X. (2025). Mindat.org: The open access mineralogy database to accelerate data-intensive geoscience research. American Mineralogist, 110(6), 833–844. doi:10.2138/am-2024-9486.
Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: September 6, 2026 10:41:53
Go to top of page