Kofa Mining District, Yuma County, Arizona, USAi
Regional Level Types | |
---|---|
Kofa Mining District | Mining District |
Yuma County | County |
Arizona | State |
USA | Country |
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Latitude & Longitude (WGS84):
32° North , 113° West (est.)
Estimate based on other nearby localities or region boundaries.
Margin of Error:
~98km
Type:
KΓΆppen climate type:
Mindat Locality ID:
33516
Long-form identifier:
mindat:1:2:33516:7
GUID (UUID V4):
8282773d-9ca8-465e-be6b-f6b905c2a76b
A Au-Ag-Mn-W-Cu-Pb-F mining district located in T1-2S, R15-17W, G&SRM, in the southern/SW margin of the Kofa (S.H.) Mountains.
Mineralization within the district varies: (1) Spotty, but often high-grade, fine-grained, gold and silver mineralization in lensing quartz-calcite, brecciated rock, fissure veins cutting Cretaceous or Tertiary andesite and Mesozoic schist or slate. Minor copper and lead, and often considerable manganese and local fluorite. Wall rocks are strongly silicified; (2) Erratic and irregular manganese oxides in fracture zones in fragmented Cretaceous or Tertiary andesitic volcanics; and, (3) Spotty stringers, pods, and disseminated grains of scheelite, associated with quartz and iron oxides, in fracture zones in fragmented volcanics and schist.
Workings include 2 major mines and numerous prospects and small mines operated mainly in the late 1800's and early 1900's, with small, intermittent operations until 1954. Total estimated and recorded production of precious and base metals through 1974 would be some 779,500 tons of ore containing about 227,500 ounces Au, 103,700 ounces Ag, 3 tons of lead and one ton of copper. Over 1,000 ounces of placer gold were recovered. Manganese production was about 230 long tons of 27% Mn and about 94 short ton units of WO3. Total production s set at some $5,000,000 (period values).
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Standard Detailed Gallery Strunz Chemical ElementsCommodity 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-localities25 valid minerals.
Rock Types Recorded
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Rock list contains entries from the region specified including sub-localities
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Alphabetical List Tree DiagramDetailed Mineral List:
β Aurorite Formula: Mn2+Mn4+3O7 · 3H2O |
β Baryte Formula: BaSO4 |
β 'Biotite' Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
β Bixbyite-(Mn) Formula: Mn3+2O3 Localities: |
β Boulangerite Formula: Pb5Sb4S11 Description: Occurs in veinlets. |
β Calcite Formula: CaCO3 Localities: Black Dahlia Mine, Kofa Mining District, Yuma County, Arizona, USA Unnamed Pb prospect, Kofa Mining District, Yuma County, Arizona, USA Unnamed Fluorspar occurrence, Kofa Mining District, Yuma County, Arizona, USA King of Arizona Mine, Kofa Mining District, Yuma County, Arizona, USA Kofa Mining District, Yuma County, Arizona, USA |
β Calcite var. Manganese-bearing Calcite Formula: (Ca,Mn)CO3 Localities: Colour: Black to brown Description: Highly manganoan. References: |
β Chalcophanite Formula: ZnMn4+3O7 · 3H2O |
β 'Chlorite Group' |
β Epidote Formula: (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
β Fluorite Formula: CaF2 Localities: Reported from at least 7 localities in this region. References: |
β Galena Formula: PbS Localities: Description: Disseminated in gangue of fluorite & calcite. |
β Gold Formula: Au Localities: Reported from at least 9 localities in this region. Description: As fine-grained free gold. with silver. References: |
β Groutite Formula: Mn3+O(OH) Localities: |
β 'K Feldspar' Localities: Description: Microscopic mixture with quartz. References: |
β 'K Feldspar var. Adularia' Formula: KAlSi3O8 Localities: Description: Microscopic mixture with quartz. References: |
β Manganite Formula: Mn3+O(OH) Localities: |
β Muscovite Formula: KAl2(AlSi3O10)(OH)2 |
β Nsutite Formula: (Mn4+,Mn2+)(O,OH)2 |
β Opal Formula: SiO2 · nH2O Habit: botryoidal Colour: colorless Fluorescence: green Description: Botryoidal formations partly covered by white calcite and quartz. |
β Opal var. Opal-AN Formula: SiO2 · nH2O Habit: botryoidal Colour: colorless Fluorescence: green Description: Botryoidal formations partly covered by white calcite and quartz. |
β 'Plagioclase' Formula: (Na,Ca)[(Si,Al)AlSi2]O8 |
β Polybasite Formula: [Ag6Sb2S7][Ag9CuS4] |
β 'Psilomelane' Localities: Black Dahlia Mine, Kofa Mining District, Yuma County, Arizona, USA No. 2 vein, North Star Mine (Northstar Mine), Kofa Mining District, Yuma County, Arizona, USA North Star Mine (Northstar Mine), Kofa Mining District, Yuma County, Arizona, USA No. 2 vein, King of Arizona Mine, Kofa Mining District, Yuma County, Arizona, USA |
β Pyrite Formula: FeS2 Localities: Description: Finely disseminated in calcareous shale footwall rock. References: |
β Pyrolusite Formula: Mn4+O2 Localities: |
β Quartz Formula: SiO2 Localities: Description: Crystals in small veinlets. |
β Quartz var. Chalcedony Formula: SiO2 Description: Banded; a breccia cement. |
β Rhodochrosite Formula: MnCO3 |
β Rhodonite Formula: CaMn3Mn[Si5O15] Description: Occurs in veins in the Eichelberger exotic breccia. |
β Scheelite Formula: Ca(WO4) Localities: Description: Sparse. |
β Silver Formula: Ag Localities: Description: With gold. |
β Todorokite Formula: (Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O Localities: |
β Willemite Formula: Zn2SiO4 |
Gallery:
List of minerals arranged by Strunz 10th Edition classification
Group 1 - Elements | |||
---|---|---|---|
β | Silver | 1.AA.05 | Ag |
β | Gold | 1.AA.05 | Au |
Group 2 - Sulphides and Sulfosalts | |||
β | Galena | 2.CD.10 | PbS |
β | Pyrite | 2.EB.05a | FeS2 |
β | Polybasite | 2.GB.15 | [Ag6Sb2S7][Ag9CuS4] |
β | Boulangerite | 2.HC.15 | Pb5Sb4S11 |
Group 3 - Halides | |||
β | Fluorite | 3.AB.25 | CaF2 |
Group 4 - Oxides and Hydroxides | |||
β | Bixbyite-(Mn) | 4.CB.10 | Mn3+2O3 |
β | Quartz | 4.DA.05 | SiO2 |
β | var. Chalcedony | 4.DA.05 | SiO2 |
β | Opal var. Opal-AN | 4.DA.10 | SiO2 Β· nH2O |
β | 4.DA.10 | SiO2 Β· nH2O | |
β | Pyrolusite | 4.DB.05 | Mn4+O2 |
β | Nsutite | 4.DB.15c | (Mn4+,Mn2+)(O,OH)2 |
β | Todorokite | 4.DK.10 | (Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 Β· 3-4H2O |
β | Groutite | 4.FD.10 | Mn3+O(OH) |
β | Manganite | 4.FD.15 | Mn3+O(OH) |
β | Chalcophanite | 4.FL.20 | ZnMn4+3O7 Β· 3H2O |
β | Aurorite | 4.FL.20 | Mn2+Mn4+3O7 Β· 3H2O |
Group 5 - Nitrates and Carbonates | |||
β | Rhodochrosite | 5.AB.05 | MnCO3 |
β | Calcite var. Manganese-bearing Calcite | 5.AB.05 | (Ca,Mn)CO3 |
β | 5.AB.05 | CaCO3 | |
Group 7 - Sulphates, Chromates, Molybdates and Tungstates | |||
β | Baryte | 7.AD.35 | BaSO4 |
β | Scheelite | 7.GA.05 | Ca(WO4) |
Group 9 - Silicates | |||
β | Willemite | 9.AA.05 | Zn2SiO4 |
β | Epidote | 9.BG.05a | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
β | Rhodonite | 9.DK.05 | CaMn3Mn[Si5O15] |
β | Muscovite | 9.EC.15 | KAl2(AlSi3O10)(OH)2 |
Unclassified | |||
β | 'Plagioclase' | - | (Na,Ca)[(Si,Al)AlSi2]O8 |
β | 'K Feldspar var. Adularia' | - | KAlSi3O8 |
β | 'Psilomelane' | - | |
β | 'Chlorite Group' | - | |
β | 'Biotite' | - | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
β | 'K Feldspar' | - |
List of minerals for each chemical element
H | Hydrogen | |
---|---|---|
H | β Aurorite | Mn2+Mn34+O7 · 3H2O |
H | β Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
H | β Chalcophanite | ZnMn34+O7 · 3H2O |
H | β Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
H | β Groutite | Mn3+O(OH) |
H | β Opal var. Opal-AN | SiO2 · nH2O |
H | β Manganite | Mn3+O(OH) |
H | β Muscovite | KAl2(AlSi3O10)(OH)2 |
H | β Nsutite | (Mn4+,Mn2+)(O,OH)2 |
H | β Opal | SiO2 · nH2O |
H | β Todorokite | (Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O |
C | Carbon | |
C | β Calcite | CaCO3 |
C | β Calcite var. Manganese-bearing Calcite | (Ca,Mn)CO3 |
C | β Rhodochrosite | MnCO3 |
O | Oxygen | |
O | β K Feldspar var. Adularia | KAlSi3O8 |
O | β Aurorite | Mn2+Mn34+O7 · 3H2O |
O | β Baryte | BaSO4 |
O | β Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
O | β Bixbyite-(Mn) | Mn23+O3 |
O | β Calcite | CaCO3 |
O | β Chalcophanite | ZnMn34+O7 · 3H2O |
O | β Quartz var. Chalcedony | SiO2 |
O | β Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
O | β Groutite | Mn3+O(OH) |
O | β Opal var. Opal-AN | SiO2 · nH2O |
O | β Manganite | Mn3+O(OH) |
O | β Calcite var. Manganese-bearing Calcite | (Ca,Mn)CO3 |
O | β Muscovite | KAl2(AlSi3O10)(OH)2 |
O | β Nsutite | (Mn4+,Mn2+)(O,OH)2 |
O | β Opal | SiO2 · nH2O |
O | β Pyrolusite | Mn4+O2 |
O | β Quartz | SiO2 |
O | β Rhodochrosite | MnCO3 |
O | β Rhodonite | CaMn3Mn[Si5O15] |
O | β Scheelite | Ca(WO4) |
O | β Todorokite | (Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O |
O | β Willemite | Zn2SiO4 |
O | β Plagioclase | (Na,Ca)[(Si,Al)AlSi2]O8 |
F | Fluorine | |
F | β Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
F | β Fluorite | CaF2 |
Na | Sodium | |
Na | β Todorokite | (Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O |
Na | β Plagioclase | (Na,Ca)[(Si,Al)AlSi2]O8 |
Mg | Magnesium | |
Mg | β Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
Mg | β Todorokite | (Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O |
Al | Aluminium | |
Al | β K Feldspar var. Adularia | KAlSi3O8 |
Al | β Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
Al | β Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
Al | β Muscovite | KAl2(AlSi3O10)(OH)2 |
Al | β Todorokite | (Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O |
Al | β Plagioclase | (Na,Ca)[(Si,Al)AlSi2]O8 |
Si | Silicon | |
Si | β K Feldspar var. Adularia | KAlSi3O8 |
Si | β Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
Si | β Quartz var. Chalcedony | SiO2 |
Si | β Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
Si | β Opal var. Opal-AN | SiO2 · nH2O |
Si | β Muscovite | KAl2(AlSi3O10)(OH)2 |
Si | β Opal | SiO2 · nH2O |
Si | β Quartz | SiO2 |
Si | β Rhodonite | CaMn3Mn[Si5O15] |
Si | β Willemite | Zn2SiO4 |
Si | β Plagioclase | (Na,Ca)[(Si,Al)AlSi2]O8 |
S | Sulfur | |
S | β Baryte | BaSO4 |
S | β Boulangerite | Pb5Sb4S11 |
S | β Galena | PbS |
S | β Polybasite | [Ag6Sb2S7][Ag9CuS4] |
S | β Pyrite | FeS2 |
K | Potassium | |
K | β K Feldspar var. Adularia | KAlSi3O8 |
K | β Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
K | β Muscovite | KAl2(AlSi3O10)(OH)2 |
K | β Todorokite | (Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O |
Ca | Calcium | |
Ca | β Calcite | CaCO3 |
Ca | β Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
Ca | β Fluorite | CaF2 |
Ca | β Calcite var. Manganese-bearing Calcite | (Ca,Mn)CO3 |
Ca | β Rhodonite | CaMn3Mn[Si5O15] |
Ca | β Scheelite | Ca(WO4) |
Ca | β Todorokite | (Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O |
Ca | β Plagioclase | (Na,Ca)[(Si,Al)AlSi2]O8 |
Ti | Titanium | |
Ti | β Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
Mn | Manganese | |
Mn | β Aurorite | Mn2+Mn34+O7 · 3H2O |
Mn | β Bixbyite-(Mn) | Mn23+O3 |
Mn | β Chalcophanite | ZnMn34+O7 · 3H2O |
Mn | β Groutite | Mn3+O(OH) |
Mn | β Manganite | Mn3+O(OH) |
Mn | β Calcite var. Manganese-bearing Calcite | (Ca,Mn)CO3 |
Mn | β Nsutite | (Mn4+,Mn2+)(O,OH)2 |
Mn | β Pyrolusite | Mn4+O2 |
Mn | β Rhodochrosite | MnCO3 |
Mn | β Rhodonite | CaMn3Mn[Si5O15] |
Mn | β Todorokite | (Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O |
Fe | Iron | |
Fe | β Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
Fe | β Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
Fe | β Pyrite | FeS2 |
Cu | Copper | |
Cu | β Polybasite | [Ag6Sb2S7][Ag9CuS4] |
Zn | Zinc | |
Zn | β Chalcophanite | ZnMn34+O7 · 3H2O |
Zn | β Willemite | Zn2SiO4 |
Sr | Strontium | |
Sr | β Todorokite | (Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O |
Ag | Silver | |
Ag | β Polybasite | [Ag6Sb2S7][Ag9CuS4] |
Ag | β Silver | Ag |
Sb | Antimony | |
Sb | β Boulangerite | Pb5Sb4S11 |
Sb | β Polybasite | [Ag6Sb2S7][Ag9CuS4] |
Ba | Barium | |
Ba | β Baryte | BaSO4 |
Ba | β Todorokite | (Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O |
W | Tungsten | |
W | β Scheelite | Ca(WO4) |
Au | Gold | |
Au | β Gold | Au |
Pb | Lead | |
Pb | β Boulangerite | Pb5Sb4S11 |
Pb | β Galena | PbS |
Localities in this Region
- Arizona
- Arizona
- Yuma County
- Kofa Mining District
- Kofa Butte
- Kofa gold placers (S.H. placers)
- Lead King Mine
- Midnight Mine (Hamilton Mine)
- North Star Mine (Northstar Mine)
- Parker claim
- Quartette Mine (Independence Mine; Perseverance Mine; Quartzite Mine)
- Quartz Mine
- Schullenbacker Mica Mines
- Tungsten Mine group
- Unnamed Ag-Au mine
- Unnamed Au-Ag mine
- Unnamed Fluorspar-Pb occurrence
- Unnamed Fluorspar occurrence
- Unnamed Pb prospect
- Verdstone Mine
- Kofa Mining District
- Yuma County
Other Regions, Features and Areas containing this locality
North America
- Sonoran DesertDesert
North America PlateTectonic Plate
- Basin and Range BasinsBasin
- Mojave DomainDomain
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King of Arizona Mine, Kofa Mining District, Yuma County, Arizona, USA