Vote for your favorite mineral in #MinCup26! - Cuprite vs. Orpiment
It's a fiery match of vibrant red Cuprite and just as saturated orange Orpiment battle for your votes!
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

Plagioclase from
Big Spar No. 1 mine, Custer, Custer Mining District, Custer County, South Dakota, USA


Locality type:Mine
Classification
Species:'Plagioclase' (not an IMA approved species)
Formula:(Na,Ca)[(Si,Al)AlSi2]O8
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Plagioclase data
Locality Data:Click here to view Big Spar No. 1 mine, Custer, Custer Mining District, Custer County, South Dakota, USA
Data Identifiers
Mindat Occurrence Record ID:765826
Long-form Identifier:1:3:765826:6
GUID (UUID V4):0
Nearest other occurrences of Plagioclase
1.6km (1.0 miles) ⓘDorothy V Prospect (Van), Custer Mining District, Custer County, South Dakota, USA
2.3km (1.4 miles) ⓘDorothy Lode, Custer Mining District, Custer County, South Dakota, USA
2.9km (1.8 miles) ⓘCrown Mine (McMackin Mine), Custer, Custer Mining District, Custer County, South Dakota, USA
4.9km (3.0 miles) ⓘDalmon Mica Mine, Custer Mining District, Custer County, South Dakota, USA
4.9km (3.1 miles) ⓘInca Mine, Custer Mining District, Custer County, South Dakota, USA
5.1km (3.2 miles) ⓘLost Bonanza Mine, Custer Mining District, Custer County, South Dakota, USA
5.7km (3.5 miles) ⓘWarren Draw Mine (Warren Gulch Mine), Custer Mining District, Custer County, South Dakota, USA
5.7km (3.5 miles) ⓘHub Mine, Custer Mining District, Custer County, South Dakota, USA
6.2km (3.8 miles) ⓘWilhelm Mine, Custer Mining District, Custer County, South Dakota, USA
6.6km (4.1 miles) ⓘMilton Mine, Custer Mining District, Custer County, South Dakota, USA
References
USGS Prof Paper 297F
 
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 5, 2026 01:59:31
Go to top of page