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

Homestake Mining District, Jefferson County, Montana, USAi
Regional Level Types
Homestake Mining DistrictMining District
Jefferson CountyCounty
MontanaState
USACountry

This page is currently not sponsored. Click here to sponsor this page.
PhotosMapsSearch
08034730017272274259615.jpg
Nellie-Mascot Shed

Nellie-Mascot Group, Homestake Mining District, Jefferson County, Montana, USA
08034730017272274259615.jpg
Nellie-Mascot Shed

Nellie-Mascot Group, Homestake Mining District, Jefferson County, Montana, USA
01285410017272053077136.jpg
Nellie-Mascot Shed

Nellie-Mascot Group, Homestake Mining District, Jefferson County, Montana, USA


No description has been added for this locality. Can you add one?

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded from this region.


Mineral List

Mineral list contains entries from the region specified including sub-localities

6 valid minerals.

Rock Types Recorded


Rock list contains entries from the region specified including sub-localities

Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ Albite
Formula: Na(AlSi3O8)
ⓘ 'Allanite Group' ?
Formula: (A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)
ⓘ 'Limonite'
ⓘ Microcline
Formula: K(AlSi3O8)
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Muscovite var. Sericite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Native Gold
Formula: Au
ⓘ Native Silver
Formula: Ag
ⓘ Quartz
Formula: SiO2
ⓘ Quartz var. Amethyst
Formula: SiO2
ⓘ Quartz var. Sceptre Quartz
Formula: SiO2
ⓘ Quartz var. Smoky Quartz
Formula: SiO2

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘNative Gold1.AA.05Au
ⓘNative Silver1.AA.05Ag
Group 4 - Oxides and Hydroxides
ⓘQuartz
var. Amethyst		4.DA.05SiO2
ⓘ4.DA.05SiO2
ⓘvar. Smoky Quartz4.DA.05SiO2
ⓘvar. Sceptre Quartz4.DA.05SiO2
Group 9 - Silicates
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘvar. Sericite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘMicrocline9.FA.30K(AlSi3O8)
ⓘAlbite9.FA.35Na(AlSi3O8)
Unclassified
ⓘ'Limonite'-
ⓘ'Allanite Group' ?-(A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)

List of minerals for each chemical element

HHydrogen
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Hⓘ Allanite Group(A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)
OOxygen
Oⓘ AlbiteNa(AlSi3O8)
Oⓘ Quartz var. AmethystSiO2
Oⓘ MicroclineK(AlSi3O8)
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ QuartzSiO2
Oⓘ Quartz var. Smoky QuartzSiO2
Oⓘ Quartz var. Sceptre QuartzSiO2
Oⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Oⓘ Allanite Group(A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)
NaSodium
Naⓘ AlbiteNa(AlSi3O8)
AlAluminium
Alⓘ AlbiteNa(AlSi3O8)
Alⓘ MicroclineK(AlSi3O8)
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SiSilicon
Siⓘ AlbiteNa(AlSi3O8)
Siⓘ Quartz var. AmethystSiO2
Siⓘ MicroclineK(AlSi3O8)
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ QuartzSiO2
Siⓘ Quartz var. Smoky QuartzSiO2
Siⓘ Quartz var. Sceptre QuartzSiO2
Siⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Siⓘ Allanite Group(A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH)
KPotassium
Kⓘ MicroclineK(AlSi3O8)
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Kⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
AgSilver
Agⓘ Native SilverAg
AuGold
Auⓘ Native GoldAu

Fossils

This region is too big or complex to display the fossil list, try looking at smaller subregions.

Localities in this Region

USA
USA

Other Regions, Features and Areas that Intersect

North AmericaContinent
North America PlateTectonic Plate
USA

This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.
Quick NavTopCommoditiesMineral ListRock TypesFossilsLocalities in RegionOther Regions
 
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 06:21:51 Page updated: April 13, 2026 12:18:55
Go to top of page