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Western Margin Duluth Complex, Duluth Complex, Minnesota, USAi
Regional Level Types
Western Margin Duluth ComplexComplex
Duluth ComplexComplex
MinnesotaState
USACountry

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Latitude & Longitude (WGS84):
47° North , 92° West (est.)
Estimate based on other nearby localities or region boundaries.
Margin of Error:
~36km
GRN:
N32W46
Type:
Complex
Köppen climate type:
Dfb : Warm-summer humid continental climate
Mindat Locality ID:
167667
Long-form identifier:
mindat:1:2:167667:2
GUID (UUID V4):
0


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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

35 valid minerals.

Rock Types Recorded

Note: data is currently VERY limited. Please bear with us while we work towards adding this information!

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

Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ Actinolite
Formula: ◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ⓘ 'Amphibole Supergroup'
Formula: AB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
ⓘ 'Amphibole Supergroup var. Uralite'
Formula: AX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
ⓘ 'Apatite'
Formula: Ca5(PO4)3(Cl/F/OH)
ⓘ Augite
Formula: (CaxMgyFez)(Mgy1Fez1)Si2O6
ⓘ 'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ Bornite
Formula: Cu5FeS4
ⓘ Chalcopyrite
Formula: CuFeS2
ⓘ 'Chlorite Group'
ⓘ Cobaltite
Formula: CoAsS
ⓘ Cordierite
Formula: (Mg,Fe)2Al3(AlSi5O18)
ⓘ Covellite
Formula: CuS
ⓘ Cubanite
Formula: CuFe2S3
ⓘ Digenite
Formula: Cu9S5
ⓘ 'Fayalite-Forsterite Series'
ⓘ Forsterite
Formula: Mg2SiO4
ⓘ Galena
Formula: PbS
ⓘ Gersdorffite
Formula: NiAsS
ⓘ Graphite
Formula: C
ⓘ Ilmenite
Formula: Fe2+TiO3
Localities: Reported from at least 10 localities in this region.
ⓘ Löllingite
Formula: FeAs2
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
Localities: Reported from at least 10 localities in this region.
ⓘ Marcasite
Formula: FeS2
ⓘ Maucherite
Formula: Ni11As8
ⓘ 'Monazite Group' ?
Formula: REE(PO4)
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Muscovite var. Sericite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Native Bismuth
Formula: Bi
ⓘ Native Silver
Formula: Ag
ⓘ Nickeline
Formula: NiAs
ⓘ Pentlandite
Formula: (NixFey)Σ9S8
ⓘ 'Plagioclase'
Formula: (Na,Ca)[(Si,Al)AlSi2]O8
ⓘ Prehnite
Formula: Ca2Al2Si3O10(OH)2
ⓘ Pyrite
Formula: FeS2
ⓘ Pyrite var. Bravoite
Formula: (Fe,Ni)S2
ⓘ 'Pyroxene Group'
Formula: ADSi2O6
ⓘ Pyrrhotite
Formula: Fe1-xS
ⓘ Rammelsbergite
Formula: NiAs2
ⓘ Safflorite
Formula: (Co,Ni,Fe)As2
ⓘ 'Serpentine Subgroup'
Formula: D3[Si2O5](OH)4
ⓘ Sperrylite
Formula: PtAs2
ⓘ Sphalerite
Formula: ZnS
ⓘ Stibiopalladinite
Formula: Pd5Sb2
ⓘ Tetradymite
Formula: Bi2Te2S
ⓘ Uraninite
Formula: UO2
ⓘ Uranophane
Formula: Ca(UO2)2(SiO3OH)2 · 5H2O
Description: with uraninite and galena
ⓘ Yarrowite
Formula: Cu9S8

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘNative Silver1.AA.05Ag
ⓘNative Bismuth1.CA.05Bi
ⓘGraphite1.CB.05aC
Group 2 - Sulphides and Sulfosalts
ⓘMaucherite2.AB.15Ni11As8
ⓘStibiopalladinite2.AC.20aPd5Sb2
ⓘDigenite2.BA.10Cu9S5
ⓘBornite2.BA.15Cu5FeS4
ⓘPentlandite2.BB.15(NixFey)Σ9S8
ⓘCovellite2.CA.05aCuS
ⓘYarrowite2.CA.05dCu9S8
ⓘSphalerite2.CB.05aZnS
ⓘChalcopyrite2.CB.10aCuFeS2
ⓘCubanite2.CB.55aCuFe2S3
ⓘNickeline2.CC.05NiAs
ⓘPyrrhotite2.CC.10Fe1-xS
ⓘGalena2.CD.10PbS
ⓘTetradymite2.DC.05Bi2Te2S
ⓘPyrite
var. Bravoite		2.EB.05a(Fe,Ni)S2
ⓘ2.EB.05aFeS2
ⓘSperrylite2.EB.05aPtAs2
ⓘMarcasite2.EB.10aFeS2
ⓘLöllingite2.EB.15aFeAs2
ⓘRammelsbergite2.EB.15aNiAs2
ⓘSafflorite2.EB.15a(Co,Ni,Fe)As2
ⓘCobaltite2.EB.25CoAsS
ⓘGersdorffite2.EB.25NiAsS
Group 4 - Oxides and Hydroxides
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘIlmenite4.CB.05Fe2+TiO3
ⓘUraninite4.DL.05UO2
Group 9 - Silicates
ⓘForsterite9.AC.05Mg2SiO4
ⓘUranophane9.AK.15Ca(UO2)2(SiO3OH)2 · 5H2O
ⓘCordierite9.CJ.10(Mg,Fe)2Al3(AlSi5O18)
ⓘAugite9.DA.15(CaxMgyFez)(Mgy1Fez1)Si2O6
ⓘActinolite9.DE.10◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ⓘPrehnite9.DP.20Ca2Al2Si3O10(OH)2
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘvar. Sericite9.EC.15KAl2(AlSi3O10)(OH)2
Unclassified
ⓘ'Amphibole Supergroup'-AB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
ⓘ'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ'Chlorite Group'-
ⓘ'Monazite Group' ?-REE(PO4)
ⓘ'Amphibole Supergroup
var. Uralite'		-AX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
ⓘ'Fayalite-Forsterite Series'-
ⓘ'Plagioclase'-(Na,Ca)[(Si,Al)AlSi2]O8
ⓘ'Pyroxene Group'-ADSi2O6
ⓘ'Serpentine Subgroup'-D3[Si2O5](OH)4
ⓘ'Apatite'-Ca5(PO4)3(Cl/F/OH)

List of minerals for each chemical element

HHydrogen
Hⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Hⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Hⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ PrehniteCa2Al2Si3O10(OH)2
Hⓘ Amphibole Supergroup var. UraliteAX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Hⓘ UranophaneCa(UO2)2(SiO3OH)2 · 5H2O
Hⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Hⓘ Serpentine SubgroupD3[Si2O5](OH)4
Hⓘ ApatiteCa5(PO4)3(Cl/F/OH)
CCarbon
Cⓘ GraphiteC
OOxygen
Oⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Oⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Oⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Oⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Oⓘ Cordierite(Mg,Fe)2Al3(AlSi5O18)
Oⓘ ForsteriteMg2SiO4
Oⓘ IlmeniteFe2+TiO3
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ Monazite GroupREE(PO4)
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ PrehniteCa2Al2Si3O10(OH)2
Oⓘ Amphibole Supergroup var. UraliteAX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Oⓘ UraniniteUO2
Oⓘ UranophaneCa(UO2)2(SiO3OH)2 · 5H2O
Oⓘ Fayalite-Forsterite Series
Oⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Oⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
Oⓘ Pyroxene GroupADSi2O6
Oⓘ Serpentine SubgroupD3[Si2O5](OH)4
Oⓘ ApatiteCa5(PO4)3(Cl/F/OH)
FFluorine
Fⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Fⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Fⓘ Amphibole Supergroup var. UraliteAX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Fⓘ ApatiteCa5(PO4)3(Cl/F/OH)
NaSodium
Naⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
MgMagnesium
Mgⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Mgⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Mgⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Mgⓘ Cordierite(Mg,Fe)2Al3(AlSi5O18)
Mgⓘ ForsteriteMg2SiO4
Mgⓘ Fayalite-Forsterite Series
AlAluminium
Alⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Alⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Alⓘ Cordierite(Mg,Fe)2Al3(AlSi5O18)
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ PrehniteCa2Al2Si3O10(OH)2
Alⓘ Amphibole Supergroup var. UraliteAX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Alⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Alⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
SiSilicon
Siⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Siⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Siⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Siⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Siⓘ Cordierite(Mg,Fe)2Al3(AlSi5O18)
Siⓘ ForsteriteMg2SiO4
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ PrehniteCa2Al2Si3O10(OH)2
Siⓘ Amphibole Supergroup var. UraliteAX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Siⓘ UranophaneCa(UO2)2(SiO3OH)2 · 5H2O
Siⓘ Fayalite-Forsterite Series
Siⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Siⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
Siⓘ Pyroxene GroupADSi2O6
Siⓘ Serpentine SubgroupD3[Si2O5](OH)4
PPhosphorus
Pⓘ Monazite GroupREE(PO4)
Pⓘ ApatiteCa5(PO4)3(Cl/F/OH)
SSulfur
Sⓘ BorniteCu5FeS4
Sⓘ Pyrite var. Bravoite(Fe,Ni)S2
Sⓘ ChalcopyriteCuFeS2
Sⓘ CobaltiteCoAsS
Sⓘ CovelliteCuS
Sⓘ CubaniteCuFe2S3
Sⓘ DigeniteCu9S5
Sⓘ GalenaPbS
Sⓘ GersdorffiteNiAsS
Sⓘ MarcasiteFeS2
Sⓘ Pentlandite(NixFey)Σ9S8
Sⓘ PyriteFeS2
Sⓘ PyrrhotiteFe1-xS
Sⓘ SphaleriteZnS
Sⓘ TetradymiteBi2Te2S
Sⓘ YarrowiteCu9S8
ClChlorine
Clⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Clⓘ Amphibole Supergroup var. UraliteAX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Clⓘ ApatiteCa5(PO4)3(Cl/F/OH)
KPotassium
Kⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Kⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CaCalcium
Caⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Caⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Caⓘ PrehniteCa2Al2Si3O10(OH)2
Caⓘ UranophaneCa(UO2)2(SiO3OH)2 · 5H2O
Caⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
Caⓘ ApatiteCa5(PO4)3(Cl/F/OH)
TiTitanium
Tiⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Tiⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Tiⓘ IlmeniteFe2+TiO3
Tiⓘ Amphibole Supergroup var. UraliteAX2Z5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
FeIron
Feⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Feⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Feⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Feⓘ BorniteCu5FeS4
Feⓘ Pyrite var. Bravoite(Fe,Ni)S2
Feⓘ ChalcopyriteCuFeS2
Feⓘ Cordierite(Mg,Fe)2Al3(AlSi5O18)
Feⓘ CubaniteCuFe2S3
Feⓘ IlmeniteFe2+TiO3
Feⓘ LöllingiteFeAs2
Feⓘ MagnetiteFe2+Fe23+O4
Feⓘ MarcasiteFeS2
Feⓘ Pentlandite(NixFey)Σ9S8
Feⓘ PyriteFeS2
Feⓘ PyrrhotiteFe1-xS
Feⓘ Safflorite(Co,Ni,Fe)As2
Feⓘ Fayalite-Forsterite Series
CoCobalt
Coⓘ CobaltiteCoAsS
Coⓘ Safflorite(Co,Ni,Fe)As2
NiNickel
Niⓘ Pyrite var. Bravoite(Fe,Ni)S2
Niⓘ GersdorffiteNiAsS
Niⓘ MaucheriteNi11As8
Niⓘ NickelineNiAs
Niⓘ Pentlandite(NixFey)Σ9S8
Niⓘ RammelsbergiteNiAs2
Niⓘ Safflorite(Co,Ni,Fe)As2
CuCopper
Cuⓘ BorniteCu5FeS4
Cuⓘ ChalcopyriteCuFeS2
Cuⓘ CovelliteCuS
Cuⓘ CubaniteCuFe2S3
Cuⓘ DigeniteCu9S5
Cuⓘ YarrowiteCu9S8
ZnZinc
Znⓘ SphaleriteZnS
AsArsenic
Asⓘ CobaltiteCoAsS
Asⓘ GersdorffiteNiAsS
Asⓘ LöllingiteFeAs2
Asⓘ MaucheriteNi11As8
Asⓘ NickelineNiAs
Asⓘ RammelsbergiteNiAs2
Asⓘ Safflorite(Co,Ni,Fe)As2
Asⓘ SperrylitePtAs2
PdPalladium
Pdⓘ StibiopalladinitePd5Sb2
AgSilver
Agⓘ Native SilverAg
SbAntimony
Sbⓘ StibiopalladinitePd5Sb2
TeTellurium
Teⓘ TetradymiteBi2Te2S
PtPlatinum
Ptⓘ SperrylitePtAs2
PbLead
Pbⓘ GalenaPbS
BiBismuth
Biⓘ Native BismuthBi
Biⓘ TetradymiteBi2Te2S
UUranium
Uⓘ UraniniteUO2
Uⓘ UranophaneCa(UO2)2(SiO3OH)2 · 5H2O

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

Minnesota regional copper-nickel study 1976-1979, Executive Summary
Morton, P., Hauck, S.A. (1987) PGE, Au and Ag content of Cu-Ni sulfides at the base of the Duluth Complex, northeastern Minnesota. Natural Resources Institute Technical Report NRRI/GMIN-TR-87-04, 81 pages.
Hauck, S., Severson, M., Zanko, L., Barnes, S., Morton, P. et al. (1997) An overview of the geology and oxide, sulfide, and platinum-group element mineralization along the western and northern contacts of the Duluth Complex: Geological Society of America Special Paper: 312: 137-185.
archive.leg.state.mn.us (n.d.) http://archive.leg.state.mn.us/docs/pre2003/other/792632.pdf
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