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Algomah Mine, Mass City, Ontonagon County, Michigan, USAi
Regional Level Types
Algomah MineMine
Mass CityCensus-designated Place
Ontonagon CountyCounty
MichiganState
USACountry

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PhotosMapsSearch
01872860017272027162043.jpg
Mine dumps

Algomah Mine, Mass City, Ontonagon County, Michigan, USA
01003370017401091997739.jpg
Mine dumps

Algomah Mine, Mass City, Ontonagon County, Michigan, USA
01826260017272027195569.jpg
Hoist bases

Algomah Mine, Mass City, Ontonagon County, Michigan, USA
01872860017272027162043.jpg
Mine dumps

Algomah Mine, Mass City, Ontonagon County, Michigan, USA
09414110017400315289638.jpg
Mine dumps

Algomah Mine, Mass City, Ontonagon County, Michigan, USA
01826260017272027195569.jpg
Hoist bases

Algomah Mine, Mass City, Ontonagon County, Michigan, USA
01872860017272027162043.jpg
Mine dumps

Algomah Mine, Mass City, Ontonagon County, Michigan, USA
01003370017401091997739.jpg
Mine dumps

Algomah Mine, Mass City, Ontonagon County, Michigan, USA
Latitude & Longitude (WGS84):
46° 45' 41'' North , 89° 2' 24'' West
Latitude & Longitude (decimal):
46.76140,-89.04010
GRN:
N32W44
Type:
Mine
Köppen climate type:
Dfb : Warm-summer humid continental climate
Nearest Settlements:
PlacePopulationDistance
Ontonagon1,324 (2017)24.1km
South Range746 (2017)45.6km
Hancock4,555 (2017)53.5km
Houghton7,970 (2017)53.7km
Watersmeet428 (2017)55.9km
Mindat Locality ID:
8397
Long-form identifier:
mindat:1:2:8397:6
GUID (UUID V4):
0


Introduction
An underground Cu mine consisting of one shaft located near Mass City, about 16 miles (ca. 26 km) SE of Ontonagon.

History
The "old" Algomah Mining Company was organized in 1852 and worked the mine until 1854 when the mine was deemed a failure and closed. The "new" Algomah Mining Company was organized in 1910 and work on a new shaft began almost immediately. Shortly after 1914, the mine shut down. The mine briefly reopened in 1956, but closed in 1957 after poor results.

Production
No rock was ever milled on-site, but in 1914 (just before closing), 12,467 lbs (5.65 t) of refined copper was recovered from hand-picked ore.

For the Collector
If patient, the rockhound can find secondary copper minerals such as malachite, azurite, chrysocolla, and other supergene minerals from this site. Algomah is also great for the micro collector.

Alteration
Removal of hematite, copper replacement, quartz-pumpellyite bleaching.

Deposit type
Native Cu

Rock formation(s)
Portage Lake Volcanics

Ore(s)
Concentrated in shoots (stratigraphic in amygdaloid)

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


24 valid minerals.

Rock Types Recorded

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

Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ Algodonite
Formula: (Cu1-xAsx)
ⓘ Atacamite
Formula: Cu2(OH)3Cl
ⓘ Azurite
Formula: Cu3(CO3)2(OH)2
ⓘ Calcite
Formula: CaCO3
ⓘ 'Chlorite Group'
ⓘ Chrysocolla
Formula: Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
ⓘ Crednerite
Formula: Cu+Mn3+O2
ⓘ Cuprite
Formula: Cu2O
ⓘ Datolite
Formula: CaB(SiO4)(OH)
ⓘ Dioptase
Formula: CuSiO3 · H2O
ⓘ Epidote
Formula: (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘ 'Feldspar Group'
ⓘ Hematite
Formula: Fe2O3
ⓘ 'K Feldspar'
ⓘ Kinoite
Formula: Ca2Cu2(H2O)2[Si3O10]
ⓘ Malachite
Formula: Cu2(CO3)(OH)2
ⓘ Nantokite
Formula: CuCl
ⓘ Native Copper
Formula: Cu
ⓘ Native Silver
Formula: Ag
✪ Paramelaconite
Formula: Cu1+2Cu2+2O3
Habit: Stepped tetragonal pyramids
Description: May be pseudomorphed by tenorite, cuprite and hematite. Xls to 5 cm.
ⓘ Paratacamite
Formula: Cu3(Cu,Zn)(OH)6Cl2
ⓘ Plancheite
Formula: Cu8(Si8O22)(OH)4 · H2O
ⓘ Pumpellyite-(Mg)
Formula: Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH)
ⓘ Quartz
Formula: SiO2
ⓘ Saponite
Formula: Ca0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O
ⓘ Tenorite
Formula: CuO
ⓘ Zeophyllite ?
Formula: Ca13Si10O28(OH)2F8 · 6H2O

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
ⓘAlgodonite2.AA.10a(Cu1-xAsx)
Group 3 - Halides
ⓘNantokite3.AA.05CuCl
ⓘAtacamite3.DA.10aCu2(OH)3Cl
ⓘParatacamite3.DA.10cCu3(Cu,Zn)(OH)6Cl2
Group 4 - Oxides and Hydroxides
ⓘCuprite4.AA.10Cu2O
ⓘParamelaconite4.AA.15Cu1+2Cu2+2O3
ⓘCrednerite4.AB.05Cu+Mn3+O2
ⓘTenorite4.AB.10CuO
ⓘHematite4.CB.05Fe2O3
ⓘQuartz4.DA.05SiO2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
ⓘAzurite5.BA.05Cu3(CO3)2(OH)2
ⓘMalachite5.BA.10Cu2(CO3)(OH)2
Group 9 - Silicates
ⓘDatolite9.AJ.20CaB(SiO4)(OH)
ⓘEpidote9.BG.05a(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘPumpellyite-(Mg)9.BG.20Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH)
ⓘKinoite9.BH.10Ca2Cu2(H2O)2[Si3O10]
ⓘDioptase9.CJ.30CuSiO3 · H2O
ⓘPlancheite9.DB.35Cu8(Si8O22)(OH)4 · H2O
ⓘSaponite9.EC.45Ca0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O
ⓘChrysocolla9.ED.20Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
ⓘZeophyllite ?9.EE.70Ca13Si10O28(OH)2F8 · 6H2O
Unclassified
ⓘ'Chlorite Group'-
ⓘ'Feldspar Group'-
ⓘ'K Feldspar'-

List of minerals for each chemical element

HHydrogen
Hⓘ AtacamiteCu2(OH)3Cl
Hⓘ AzuriteCu3(CO3)2(OH)2
Hⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Hⓘ DioptaseCuSiO3 · H2O
Hⓘ DatoliteCaB(SiO4)(OH)
Hⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Hⓘ KinoiteCa2Cu2(H2O)2[Si3O10]
Hⓘ MalachiteCu2(CO3)(OH)2
Hⓘ ParatacamiteCu3(Cu,Zn)(OH)6Cl2
Hⓘ PlancheiteCu8(Si8O22)(OH)4 · H2O
Hⓘ Pumpellyite-(Mg)Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH)
Hⓘ SaponiteCa0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O
Hⓘ ZeophylliteCa13Si10O28(OH)2F8 · 6H2O
BBoron
Bⓘ DatoliteCaB(SiO4)(OH)
CCarbon
Cⓘ AzuriteCu3(CO3)2(OH)2
Cⓘ CalciteCaCO3
Cⓘ MalachiteCu2(CO3)(OH)2
OOxygen
Oⓘ AtacamiteCu2(OH)3Cl
Oⓘ AzuriteCu3(CO3)2(OH)2
Oⓘ CalciteCaCO3
Oⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Oⓘ CredneriteCu+Mn3+O2
Oⓘ CupriteCu2O
Oⓘ DioptaseCuSiO3 · H2O
Oⓘ DatoliteCaB(SiO4)(OH)
Oⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Oⓘ HematiteFe2O3
Oⓘ KinoiteCa2Cu2(H2O)2[Si3O10]
Oⓘ MalachiteCu2(CO3)(OH)2
Oⓘ ParamelaconiteCu21+Cu22+O3
Oⓘ ParatacamiteCu3(Cu,Zn)(OH)6Cl2
Oⓘ PlancheiteCu8(Si8O22)(OH)4 · H2O
Oⓘ Pumpellyite-(Mg)Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH)
Oⓘ QuartzSiO2
Oⓘ SaponiteCa0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O
Oⓘ TenoriteCuO
Oⓘ ZeophylliteCa13Si10O28(OH)2F8 · 6H2O
FFluorine
Fⓘ ZeophylliteCa13Si10O28(OH)2F8 · 6H2O
MgMagnesium
Mgⓘ Pumpellyite-(Mg)Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH)
Mgⓘ SaponiteCa0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O
AlAluminium
Alⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Alⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Alⓘ Pumpellyite-(Mg)Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH)
Alⓘ SaponiteCa0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O
SiSilicon
Siⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Siⓘ DioptaseCuSiO3 · H2O
Siⓘ DatoliteCaB(SiO4)(OH)
Siⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Siⓘ KinoiteCa2Cu2(H2O)2[Si3O10]
Siⓘ PlancheiteCu8(Si8O22)(OH)4 · H2O
Siⓘ Pumpellyite-(Mg)Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH)
Siⓘ QuartzSiO2
Siⓘ SaponiteCa0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O
Siⓘ ZeophylliteCa13Si10O28(OH)2F8 · 6H2O
ClChlorine
Clⓘ AtacamiteCu2(OH)3Cl
Clⓘ NantokiteCuCl
Clⓘ ParatacamiteCu3(Cu,Zn)(OH)6Cl2
CaCalcium
Caⓘ CalciteCaCO3
Caⓘ DatoliteCaB(SiO4)(OH)
Caⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Caⓘ KinoiteCa2Cu2(H2O)2[Si3O10]
Caⓘ Pumpellyite-(Mg)Ca2MgAl2[Si2O6OH][SiO4](OH)2(OH)
Caⓘ SaponiteCa0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O
Caⓘ ZeophylliteCa13Si10O28(OH)2F8 · 6H2O
MnManganese
Mnⓘ CredneriteCu+Mn3+O2
FeIron
Feⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Feⓘ HematiteFe2O3
Feⓘ SaponiteCa0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2O
CuCopper
Cuⓘ Algodonite(Cu1-xAsx)
Cuⓘ AtacamiteCu2(OH)3Cl
Cuⓘ AzuriteCu3(CO3)2(OH)2
Cuⓘ ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Cuⓘ CredneriteCu+Mn3+O2
Cuⓘ CupriteCu2O
Cuⓘ Native CopperCu
Cuⓘ DioptaseCuSiO3 · H2O
Cuⓘ KinoiteCa2Cu2(H2O)2[Si3O10]
Cuⓘ MalachiteCu2(CO3)(OH)2
Cuⓘ NantokiteCuCl
Cuⓘ ParamelaconiteCu21+Cu22+O3
Cuⓘ ParatacamiteCu3(Cu,Zn)(OH)6Cl2
Cuⓘ PlancheiteCu8(Si8O22)(OH)4 · H2O
Cuⓘ TenoriteCuO
ZnZinc
Znⓘ ParatacamiteCu3(Cu,Zn)(OH)6Cl2
AsArsenic
Asⓘ Algodonite(Cu1-xAsx)
AgSilver
Agⓘ Native SilverAg

Other Databases

Link to USGS MRDS:10080402

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

pubs.er.usgs.gov (n.d.) https://pubs.er.usgs.gov/publication/pp144 - United States Geological Survey Professional Paper 144.
Butler, B.S., Burbank, W.S. (1929) The Copper Deposits of Michigan. U.S. Geological Survey. Professional Paper 144. 238 pp.
Copper Range Exploration Company (1968) Bedrock Geology Map of the Southeast Quarter of the White Pine Quadrangle, Ontonagon County, Michigan. Geology mapped and compiled by the Copper Range Exploration Company, Inc., and by H. Hubbard (United States Geological Survey) (Unpublished).
Wilband, J.T. (1978) The Copper Resources of Northern Michigan. United States Bureau of Mines Open File Report. Contract No. J0366067. 66 pages.
Morris, Tom (1983) Michigan Mineralogy. A locality Index. Rocks & Minerals, 58 (3). 107-113 doi:10.1080/00357529.1983.11767128p.112
Johnson, A.M., Groth, E.H. (1998) Inventory of Underground Mines, Ontonagon County. Michigan Department of Natural Resources: 7-11.
Heinrich, E. W., Robinson, George Willard (2004) Mineralogy of Michigan (2nd ed.) A.E. Seaman Mineral Museum and Michigan Technological University. 252pp.
Kaminski-Hamka, T. (2011) The Copper Mines of Ontonagon County, Michigan. Copperlady Press. 154 pages.
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