Log InRegister
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
Home PageAbout MindatThe Mindat ManualHistory of MindatCopyright StatusWho We AreOur ScienceMindat Newsletter [Free Download]Contact Us
Donate to MindatSponsor a PageCorporate SponsorshipSponsored Pages
Learning CenterWhat Is a Mineral?The Most Common Minerals on EarthInformation for EducatorsMindat ArticlesMindat Newsletter [Free Download]The ElementsThe Mineral Quiz
Search FormMinerals by PropertiesMinerals by ChemistryMineral Visual ExplorerAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDMinerals by CountryAlphabetical Mineral IndexAlphabetical Locality SearchMineral Association SearchList of CountriesLocalities Near MePhoto SearchSearch ArticlesSearch GlossaryThe Rock H. Currier Digital LibraryMore Search Options
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
MineralsPetrologyFossilsMeteoritesGeologic Time
Mining CompaniesStatisticsMineral MuseumsClubs & OrganizationsMineral Shows & EventsDevice SettingsTime Machine
Read DiscussionsIdentification Request
Photo SearchPhoto GalleriesSearch by ColourPhoto Colour ExplorerNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day GalleryPhotography

St. Croix County, Wisconsin, USAi
Regional Level Types
St. Croix CountyCounty
WisconsinState
USACountry

This page is currently not sponsored. Click here to sponsor this page.
PhotosMapsSearchMineralogy
02530220017272084875980.jpg
The Baldwin Boulder

St. Croix County, Wisconsin, USA
05571640017272084872280.jpg
River Falls "Monument"

River Falls, St. Croix County, Wisconsin, USA
09376220017272084873875.jpg
Cudd's Quarry, 1975

Cudd's Quarry, River Falls, St. Croix County, Wisconsin, USA
02530220017272084875980.jpg
The Baldwin Boulder

St. Croix County, Wisconsin, USA
05571640017272084872280.jpg
River Falls "Monument"

River Falls, St. Croix County, Wisconsin, USA
09376220017272084873875.jpg
Cudd's Quarry, 1975

Cudd's Quarry, River Falls, St. Croix County, Wisconsin, USA
03105730017272084883207.jpg
The Baldwin Boulder

St. Croix County, Wisconsin, USA
06105080017272084886130.jpg
River Falls "Monument"

River Falls, St. Croix County, Wisconsin, USA
Neighbouring regions:
Barron County, Wisconsin, USA
Polk County, Wisconsin, USA
Pierce County, Wisconsin, USA
Dunn County, Wisconsin, USA
Washington County, Minnesota, USA
Type:
County
Largest Settlements:
PlacePopulation
Hudson13,566 (2017)
New Richmond8,821 (2017)
Baldwin3,972 (2017)
North Hudson3,822 (2017)
Somerset2,693 (2017)
Hammond1,898 (2017)
Mindat Locality ID:
59414
Long-form identifier:
mindat:1:2:59414:0
GUID (UUID V4):
0
Other Languages:
View 28 more...
French:
comté de Sainte-Croix, Wisconsin, États-Unis
German:
St. Croix County, Wisconsin, Vereinigte Staaten
Italian:
contea di St. Croix, Wisconsin, Stati Uniti d'America
Russian:
Санта-Крус, Висконсин, Соединённые Штаты Америки
Simplified Chinese:
聖克羅伊縣, 威斯康辛州, 美国
Spanish:
Condado de St. Croix, Wisconsin, Estados Unidos
Albanian:
St. Croix County, Wisconsin, Shtetet e Bashkuara të Amerikës
Arabic:
مقاطعة سانت كروا , ويسكونسن, الولايات المتحدة
Basque:
St. Croix konderria , Wisconsin
Bavarian:
St, Wisconsin, Vaoanigte Stootn
Bishnupriya Manipuri:
সেন্ট ক্রয়িক্স কাউন্টি, উইসকনসিন, তিলপারাষ্ট্র
Bulgarian:
Сейнт Крой, Уисконсин, Съединени американски щати
Cebuano:
Saint Croix County, Wisconsin
Dutch:
St. Croix County, Wisconsin, Verenigde Staten
Esperanto:
Kantono Sankta Kruco, Viskonsino
Farsi/Persian:
شهرستان سنت کریکس، ویسکانسین, ویسکانسین, ایالات متحده آمریکا
Hungarian:
Saint Croix megye, Wisconsin, Amerikai Egyesült Államok
Japanese:
セントクロワ郡, ウィスコンシン州, アメリカ合衆国
Latin:
St. Croix Comitatus, Visconsinia, Civitates Foederatae Americae
Low Saxon/Low German:
St. Croix County, Wisconsin, USA
Min Dong Chinese:
St. Croix Gông, Wisconsin
Minnan / Hokkien-Taiwanese:
St. Croix Kūn
Norwegian:
St. Croix County, Wisconsin, USA
Polish:
Hrabstwo St. Croix, Wisconsin, Stany Zjednoczone
Portuguese:
Condado de St. Croix, Wisconsin, Estados Unidos
Romanian:
Comitatul St. Croix, Wisconsin, Statele Unite ale Americii
Sardinian:
contea de St. Croix, Wisconsin, Istados Unidos de Amèrica
Serbian:
St. Croix County, Висконсин, Сједињене Америчке Државе
Serbo-Croatian:
St. Croix County, Wisconsin, Sjedinjene Američke Države
Swedish:
St. Croix County, Wisconsin, USA
Ukrainian:
Сент-Круа, Вісконсин, Сполучені Штати Америки
Urdu:
سینٹ کروا کاؤنٹی، وسکونسن, وسکونسن, ریاستہائے متحدہ امریکا
Vietnamese:
Quận St. Croix, Wisconsin, Chủng Quốc Hoa Kỳ
Waray:
Condado han St. Croix, Wisconsin, Estados Unidos


St. Croix County is underlain by Cambrian and Ordovician sedimentary rocks. The Cambrian sediments are largely sandstones, often glauconitic. The Ordovician section tends to be carbonate dominated, with the notable exception of the super-mature St. Peter Sandstone. The carbonates are quarried for crushed stone. Calcite and drusy quartz can be found in these rocks.

Several faults originally of Keweenawan age, but reactived in post-Ordovician time, shift Cambrian and Ordovician strata. The most notable is the Hastings - Hudson Fault, traceable near Hudson and through Willow River State Park.

The Wisconsinan St. Croix moraine cuts through the county near the Interstate 94 corridor. The landscape south of there is bedrock dominated with only thin older glacial drift. North of the interstate the terrain is dominated by glacial landforms. Interesting materials can be found in the glacial drift including iron formation, float copper, omars, jasper and "Lake Superior" agates.

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

10 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:

ⓘ Aragonite
Formula: CaCO3
ⓘ Calcite
Formula: CaCO3
ⓘ Dolomite
Formula: CaMg(CO3)2
ⓘ 'Glauconite'
Formula: K0.60-0.85(Fe3+,Mg,Al)2(Si,Al)4O10](OH)2
ⓘ Goethite
Formula: Fe3+O(OH)
ⓘ Marcasite
Formula: FeS2
ⓘ Native Copper
Formula: Cu
ⓘ Native Iron
Formula: Fe
ⓘ Pyrite
Formula: FeS2
ⓘ Quartz
Formula: SiO2
Localities: Reported from at least 6 localities in this region.
ⓘ Quartz var. Agate
Formula: SiO2
ⓘ Quartz var. Chalcedony
Formula: SiO2
ⓘ Troilite
Formula: FeS

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘNative Copper1.AA.05Cu
ⓘNative Iron1.AE.05Fe
Group 2 - Sulphides and Sulfosalts
ⓘTroilite2.CC.10FeS
ⓘPyrite2.EB.05aFeS2
ⓘMarcasite2.EB.10aFeS2
Group 4 - Oxides and Hydroxides
ⓘGoethite4.00.Fe3+O(OH)
ⓘQuartz
var. Agate		4.DA.05SiO2
ⓘvar. Chalcedony4.DA.05SiO2
ⓘ4.DA.05SiO2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
ⓘDolomite5.AB.10CaMg(CO3)2
ⓘAragonite5.AB.15CaCO3
Unclassified
ⓘ'Glauconite'-K0.60-0.85(Fe3+,Mg,Al)2(Si,Al)4O10](OH)2

List of minerals for each chemical element

HHydrogen
Hⓘ GlauconiteK0.60-0.85(Fe3+,Mg,Al)2(Si,Al)4O10](OH)2
Hⓘ GoethiteFe3+O(OH)
CCarbon
Cⓘ AragoniteCaCO3
Cⓘ CalciteCaCO3
Cⓘ DolomiteCaMg(CO3)2
OOxygen
Oⓘ Quartz var. AgateSiO2
Oⓘ AragoniteCaCO3
Oⓘ CalciteCaCO3
Oⓘ Quartz var. ChalcedonySiO2
Oⓘ DolomiteCaMg(CO3)2
Oⓘ GlauconiteK0.60-0.85(Fe3+,Mg,Al)2(Si,Al)4O10](OH)2
Oⓘ GoethiteFe3+O(OH)
Oⓘ QuartzSiO2
MgMagnesium
Mgⓘ DolomiteCaMg(CO3)2
Mgⓘ GlauconiteK0.60-0.85(Fe3+,Mg,Al)2(Si,Al)4O10](OH)2
AlAluminium
Alⓘ GlauconiteK0.60-0.85(Fe3+,Mg,Al)2(Si,Al)4O10](OH)2
SiSilicon
Siⓘ Quartz var. AgateSiO2
Siⓘ Quartz var. ChalcedonySiO2
Siⓘ GlauconiteK0.60-0.85(Fe3+,Mg,Al)2(Si,Al)4O10](OH)2
Siⓘ QuartzSiO2
SSulfur
Sⓘ MarcasiteFeS2
Sⓘ PyriteFeS2
Sⓘ TroiliteFeS
KPotassium
Kⓘ GlauconiteK0.60-0.85(Fe3+,Mg,Al)2(Si,Al)4O10](OH)2
CaCalcium
Caⓘ AragoniteCaCO3
Caⓘ CalciteCaCO3
Caⓘ DolomiteCaMg(CO3)2
FeIron
Feⓘ GlauconiteK0.60-0.85(Fe3+,Mg,Al)2(Si,Al)4O10](OH)2
Feⓘ GoethiteFe3+O(OH)
Feⓘ Native IronFe
Feⓘ MarcasiteFeS2
Feⓘ PyriteFeS2
Feⓘ TroiliteFeS
CuCopper
Cuⓘ Native CopperCu

Fossils

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

Other Databases

Wikipedia:https://en.wikipedia.org/wiki/St._Croix_County,_Wisconsin
Wikidata ID:Q591156
GeoNames ID:5270199

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.

References

Hurley,P.M.,Cormier,R.F.,Hower,J.,Fairbairn,H.W.,and Pinson,W.H.,Jr.,(1960) Reliability of glauconite for age measurement by K-Ar and Rb-Sr methods :American Association of Petroleum Geologists Bulletin,v.44,p.1793-1808
Dott, R. & J. Attig (2004) Roadside Geology of Wisconsin: Mountain Press, 346 p.
Quick NavTopCommoditiesMineral ListRock TypesFossilsOther DatabasesLocalities in RegionOther RegionsReferences
 
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: October 21, 2026 07:41:02 Page updated: July 27, 2026 05:17:04
Go to top of page