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Northwestern Mine, Central, Houghton Township, Keweenaw County, Michigan, USAi
Regional Level Types
Northwestern MineMine
CentralUnincorporated Community
Houghton TownshipTownship
Keweenaw CountyCounty
MichiganState
USACountry

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PhotosMapsSearch
09423750017272042094680.jpg
Northwestern Mine rock pile

Northwestern Mine, Central, Houghton Township, Keweenaw County, Michigan, USA
05494470017272042105147.jpg
Rock pile at the Northwestern

Northwestern Mine, Central, Houghton Township, Keweenaw County, Michigan, USA
02264050017272042111713.jpg
The Pile

Northwestern Mine, Central, Houghton Township, Keweenaw County, Michigan, USA
09423750017272042094680.jpg
Northwestern Mine rock pile

Northwestern Mine, Central, Houghton Township, Keweenaw County, Michigan, USA
05494470017272042105147.jpg
Rock pile at the Northwestern

Northwestern Mine, Central, Houghton Township, Keweenaw County, Michigan, USA
02264050017272042111713.jpg
The Pile

Northwestern Mine, Central, Houghton Township, Keweenaw County, Michigan, USA
09423750017272042094680.jpg
Northwestern Mine rock pile

Northwestern Mine, Central, Houghton Township, Keweenaw County, Michigan, USA
05494470017272042105147.jpg
Rock pile at the Northwestern

Northwestern Mine, Central, Houghton Township, Keweenaw County, Michigan, USA
Latitude & Longitude (WGS84):
47° 24' 32'' North , 88° 11' 29'' West
Latitude & Longitude (decimal):
47.40889,-88.19139
GRN:
N32W44
Type:
Mine
Köppen climate type:
Dfb : Warm-summer humid continental climate
Nearest Settlements:
PlacePopulationDistance
Ahmeek146 (2017)19.7km
Copper City187 (2017)20.3km
Copper Harbor108 (2017)23.7km
Calumet703 (2017)26.8km
Laurium1,941 (2017)26.9km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Copper Country Rock and Mineral ClubDollar Bay, Michigan40km
Mindat Locality ID:
17095
Long-form identifier:
mindat:1:2:17095:9
GUID (UUID V4):
0


The Northwestern Mine consists of 4 shafts and at least 1 adit. The Northwestern Mining Company was organized in 1845 and then reorganized in 1848. Work continued until 1857 and resumed again in 1863. All work ceased in 1865 and was absorbed by the Central Mining Company shortly after. 313,000 lbs. of refined copper was recovered from the mine. Copper, silver, analcime, and prehnite can be found on the poor-rock piles.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.


Mineral List


14 valid minerals.

Detailed Mineral List:

ⓘ Analcime
Formula: Na(AlSi2O6) · H2O
Habit: trapazohedra to 2.5cm in diameter
Colour: reddish
ⓘ 'Apophyllite Group'
Formula: AB4[Si8O22]X · 8H2O
ⓘ Calcite
Formula: CaCO3
ⓘ Chalcocite
Formula: Cu2S
ⓘ 'Chlorite Group'
ⓘ Chrysocolla
Formula: Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
ⓘ Cuprite
Formula: Cu2O
References:
Frank KarastiIdentified by Frank Karasti: Visual Identification
ⓘ Datolite
Formula: CaB(SiO4)(OH)
ⓘ 'K Feldspar'
ⓘ 'K Feldspar var. Adularia'
Formula: KAlSi3O8
ⓘ Malachite
Formula: Cu2(CO3)(OH)2
References:
Frank KarastiIdentified by Frank Karasti: Visual Identification
ⓘ Microcline
Formula: K(AlSi3O8)
ⓘ Native Copper
Formula: Cu
ⓘ Native Silver
Formula: Ag
ⓘ Prehnite
Formula: Ca2Al2Si3O10(OH)2
ⓘ Pumpellyite-(Mg)
Formula: Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH)
ⓘ Pumpellyite-(Mg) var. Chlorastrolite
Formula: Ca2MgAl2(Si2O7)(SiO4)(OH)2 · H2O
ⓘ 'Pumpellyite Subgroup'
Formula: Ca2XAl2[Si2O6(OH)][SiO4](OH)2A
ⓘ Quartz
Formula: SiO2
ⓘ Saponite
Formula: Ca0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘNative Copper1.AA.05Cu
ⓘNative Silver1.AA.05Ag
Group 2 - Sulphides and Sulfosalts
ⓘChalcocite2.BA.05Cu2S
Group 4 - Oxides and Hydroxides
ⓘCuprite4.AA.10Cu2O
ⓘQuartz4.DA.05SiO2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
ⓘMalachite5.BA.10Cu2(CO3)(OH)2
Group 9 - Silicates
ⓘDatolite9.AJ.20CaB(SiO4)(OH)
ⓘPumpellyite-(Mg)9.BG.20Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH)
ⓘvar. Chlorastrolite9.BG.20Ca2MgAl2(Si2O7)(SiO4)(OH)2 · H2O
ⓘPrehnite9.DP.20Ca2Al2Si3O10(OH)2
ⓘSaponite9.EC.45Ca0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O
ⓘChrysocolla9.ED.20Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
ⓘMicrocline9.FA.30K(AlSi3O8)
ⓘAnalcime9.GB.05Na(AlSi2O6) · H2O
Unclassified
ⓘ'K Feldspar
var. Adularia'		-KAlSi3O8
ⓘ'Apophyllite Group'-AB4[Si8O22]X · 8H2O
ⓘ'Chlorite Group'-
ⓘ'Pumpellyite Subgroup'-Ca2XAl2[Si2O6(OH)][SiO4](OH)2A
ⓘ'K Feldspar'-

List of minerals for each chemical element

HHydrogen
Hⓘ AnalcimeNa(AlSi2O6) · H2O
Hⓘ Apophyllite GroupAB4[Si8O22]X · 8H2O
Hⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Hⓘ DatoliteCaB(SiO4)(OH)
Hⓘ MalachiteCu2(CO3)(OH)2
Hⓘ PrehniteCa2Al2Si3O10(OH)2
Hⓘ Pumpellyite SubgroupCa2XAl2[Si2O6(OH)][SiO4](OH)2A
Hⓘ Pumpellyite-(Mg)Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH)
Hⓘ SaponiteCa0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O
Hⓘ Pumpellyite-(Mg) var. ChlorastroliteCa2MgAl2(Si2O7)(SiO4)(OH)2 · H2O
BBoron
Bⓘ DatoliteCaB(SiO4)(OH)
CCarbon
Cⓘ CalciteCaCO3
Cⓘ MalachiteCu2(CO3)(OH)2
OOxygen
Oⓘ K Feldspar var. AdulariaKAlSi3O8
Oⓘ AnalcimeNa(AlSi2O6) · H2O
Oⓘ Apophyllite GroupAB4[Si8O22]X · 8H2O
Oⓘ CalciteCaCO3
Oⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Oⓘ CupriteCu2O
Oⓘ DatoliteCaB(SiO4)(OH)
Oⓘ MalachiteCu2(CO3)(OH)2
Oⓘ MicroclineK(AlSi3O8)
Oⓘ PrehniteCa2Al2Si3O10(OH)2
Oⓘ Pumpellyite SubgroupCa2XAl2[Si2O6(OH)][SiO4](OH)2A
Oⓘ Pumpellyite-(Mg)Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH)
Oⓘ QuartzSiO2
Oⓘ SaponiteCa0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O
Oⓘ Pumpellyite-(Mg) var. ChlorastroliteCa2MgAl2(Si2O7)(SiO4)(OH)2 · H2O
NaSodium
Naⓘ AnalcimeNa(AlSi2O6) · H2O
MgMagnesium
Mgⓘ Pumpellyite-(Mg)Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH)
Mgⓘ SaponiteCa0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O
Mgⓘ Pumpellyite-(Mg) var. ChlorastroliteCa2MgAl2(Si2O7)(SiO4)(OH)2 · H2O
AlAluminium
Alⓘ K Feldspar var. AdulariaKAlSi3O8
Alⓘ AnalcimeNa(AlSi2O6) · H2O
Alⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Alⓘ MicroclineK(AlSi3O8)
Alⓘ PrehniteCa2Al2Si3O10(OH)2
Alⓘ Pumpellyite SubgroupCa2XAl2[Si2O6(OH)][SiO4](OH)2A
Alⓘ Pumpellyite-(Mg)Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH)
Alⓘ SaponiteCa0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O
Alⓘ Pumpellyite-(Mg) var. ChlorastroliteCa2MgAl2(Si2O7)(SiO4)(OH)2 · H2O
SiSilicon
Siⓘ K Feldspar var. AdulariaKAlSi3O8
Siⓘ AnalcimeNa(AlSi2O6) · H2O
Siⓘ Apophyllite GroupAB4[Si8O22]X · 8H2O
Siⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Siⓘ DatoliteCaB(SiO4)(OH)
Siⓘ MicroclineK(AlSi3O8)
Siⓘ PrehniteCa2Al2Si3O10(OH)2
Siⓘ Pumpellyite SubgroupCa2XAl2[Si2O6(OH)][SiO4](OH)2A
Siⓘ Pumpellyite-(Mg)Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH)
Siⓘ QuartzSiO2
Siⓘ SaponiteCa0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O
Siⓘ Pumpellyite-(Mg) var. ChlorastroliteCa2MgAl2(Si2O7)(SiO4)(OH)2 · H2O
SSulfur
Sⓘ ChalcociteCu2S
KPotassium
Kⓘ K Feldspar var. AdulariaKAlSi3O8
Kⓘ MicroclineK(AlSi3O8)
CaCalcium
Caⓘ CalciteCaCO3
Caⓘ DatoliteCaB(SiO4)(OH)
Caⓘ PrehniteCa2Al2Si3O10(OH)2
Caⓘ Pumpellyite SubgroupCa2XAl2[Si2O6(OH)][SiO4](OH)2A
Caⓘ Pumpellyite-(Mg)Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH)
Caⓘ SaponiteCa0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O
Caⓘ Pumpellyite-(Mg) var. ChlorastroliteCa2MgAl2(Si2O7)(SiO4)(OH)2 · H2O
FeIron
Feⓘ SaponiteCa0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O
CuCopper
Cuⓘ ChalcociteCu2S
Cuⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Cuⓘ CupriteCu2O
Cuⓘ Native CopperCu
Cuⓘ MalachiteCu2(CO3)(OH)2
AgSilver
Agⓘ Native SilverAg

Other Regions, Features and Areas containing this locality

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

Henwood, W.J. (1871) Observations on Metalliferous Deposits: On the Native Copper of Lake Superior. Transactions of the Royal Geological Society of Cornwall 8(1): 385-489.
Butler, B.S., Burbank, W.S. (1929) The Copper Deposits of Michigan. U.S. Geological Survey. Professional Paper 144. 238 pp.
Tschernich, Rudy W. (1992) Zeolites of the World. Geoscience Press, Inc. 567pp.
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