Vote for your favorite mineral in #MinCup26! - Bournonite vs. Vesuvianite
Cogwheels of bournonite are up against colourful vesuvianite.
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
Knowles lode claim, Custer, Custer Mining District, Custer County, South Dakota, USA


Locality type:Claim
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 Knowles lode claim, Custer, Custer Mining District, Custer County, South Dakota, USA
Data Identifiers
Mindat Occurrence Record ID:211405
Long-form Identifier:1:3:211405:7
GUID (UUID V4):0
Nearest other occurrences of Biotite
0.2km (0.1 miles) ⓘSunshine Mica Prospect, Custer Mining District, Custer County, South Dakota, USA
0.5km (0.3 miles) ⓘSurprise Mica Mine, Custer Mining District, Custer County, South Dakota, USA
1.4km (0.8 miles) ⓘBig Horn Lode Prospect, Custer Mining District, Custer County, South Dakota, USA
4.1km (2.6 miles) ⓘLucky Star Prospect, Custer Mining District, Custer County, South Dakota, USA
4.4km (2.7 miles) ⓘDorothy V Prospect (Van), Custer Mining District, Custer County, South Dakota, USA
4.8km (3.0 miles) ⓘBurgess Mica Prospect, Custer Mining District, Custer County, South Dakota, USA
5.5km (3.4 miles) ⓘHofert Arcade (Victory No. 1 Prospect), Custer Mining District, Custer County, South Dakota, USA
5.8km (3.6 miles) ⓘBuster lode (Buster Dike Mica Mine), Custer, Custer Mining District, Custer County, South Dakota, USA
6.4km (4.0 miles) ⓘWhite Bear Mine (Gamber Mine), Custer, Custer Mining District, Custer County, South Dakota, USA
7.0km (4.3 miles) ⓘSilver Dollar Mine, Custer Mining District, Custer County, South Dakota, USA
References
Smith, Arthur E., Fritzsch, Eric (2000) SOUTH DAKOTA. Rocks & Minerals, 75 (3) 156-169 doi:10.1080/00357520009605635
 
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 4, 2026 05:04:09
Go to top of page