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Lakeshore Mine, North Komelik area, Casa Grande Mining District, Pinal County, Arizona, USAi
Regional Level Types
Lakeshore MineMine
North Komelik areaArea
Casa Grande Mining DistrictMining District
Pinal CountyCounty
ArizonaState
USACountry

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Latitude & Longitude (WGS84):
32° 31' 23'' North , 111° 54' 6'' West
Latitude & Longitude (decimal):
Type:
Köppen climate type:
Nearest Settlements:
PlacePopulationDistance
Anegam151 (2011)20.6km
Vaiva Vo128 (2011)21.8km
Santa Rosa628 (2011)25.7km
Chuichu269 (2011)27.8km
Arizona City10,475 (2011)33.7km
Mindat Locality ID:
51058
Long-form identifier:
mindat:1:2:51058:2
GUID (UUID V4):
0
Other/historical names associated with this locality:
Casa Grande Mine; Trans Arizona Res. Inc. Mine; Treasure State Mine; Cyprus Casa Grande Mine; Tohono Mine; Cyprus Tohono Mine


A former surface and underground Cu-Mo-Au-Ag-Pb-Zn mine located in the SE¼ sec. 25, and secs. 26, 35 & 36, T10S, R4E (Silver Reef Mts 15 minute topo map), approximately 2 miles SE of North Komelik. Discovered in 1966 by the El Paso Natural Gas Co. Produced 1974-1986. Previous operator was the Hecla Mining Co. and Noranda Lakeshore Mines, Inc. (1983). The ore outcrop in the bottom of a shallow arroyo was discovered in the early 1880's by Trout & Achinson. Based from the Tohono O'odham Indians 6 patented and 19 unpatented lode claims encompasing 402 acres; in addition 10,142 acres were leased from the Tohono O'odham Indians.

Mineralization is a skarn-related porphyry copper deposit with an irregular, pipe-shaped ore body hosted in Mescal Limestone and diabase. The ore body is 914.4 meters thick, plunges 20 degrees, with a depth-to-bottom of 914.4 meters and a length of 1219.2 meters. Ore control was faulting and stratigraphic control. Alteration is oxidation, potassic, phyllic, argillic, sericitization and propyllitic zones.

Area structures include the Lakeshore Fault (NNW strike, dip 50-80W). Post-ore faulting dropped stock down to the west.

Workings are least 900 feet deep.

Assay data: 0.76% Cu in sulfide ore, 1.03% Cu in oxide ore (1976). Ore reserves were placed at 9,977,000 metric tons (1983).

The deposit has 3 principal parts: 1) a core of disseminated sulfide ore in quartz monzonite; 2) a tactite ore in Paleozoic and Precambrian sediments at the base and marginal to the thick sulfide deposit; and 3) an enriched blanket of oxide ore formed by oxidation of a secondary enriched chalcocite blanket overlying the core. A high-value reverse fault offsets the overlying oxide zone to the west from the central sulfide zone on the east. Pyrite: chalcopyrite suggests a pyrite halo. USBM gives orebody dimensions as: 6000 feet long, 1080 feet thick, 2500 feet wide, and 500 feet deep.

Oxide ore was mined by open pit methods in early production, sulfide and tactite ore by room & pillar, block caving. In 1884 the mine had a 112 foot deep shaft & drifting. In 1914 a new vertical shaft was sunk to 285 feet. In 1993 and an in-situ leach operation was started. Further property evaluation was undertaken in 1993.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


29 valid minerals.

Detailed Mineral List:

Anhydrite
Formula: CaSO4
Atacamite
Formula: Cu2(OH)3Cl
Description: An isolated occurrence on the 900 level in the 'brochantite zone.'
'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Bornite
Formula: Cu5FeS4
Brochantite
Formula: Cu4(SO4)(OH)6
Description: Occurs on the 900 level in the 'brochantite zone.'
Calcite
Formula: CaCO3
Chalcocite
Formula: Cu2S
Chalcopyrite
Formula: CuFeS2
'Chlorite Group'
Chondrodite
Formula: Mg5(SiO4)2F2
Description: Locally abundant in forsterite marble.
Chrysocolla
Formula: Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Covellite
Formula: CuS
Cuprite
Formula: Cu2O
Diopside
Formula: CaMgSi2O6
Dioptase
Formula: CuSiO3 · H2O
Forsterite
Formula: Mg2SiO4
Description: Locally abundant in some portions of metadolomites.
Galena
Formula: PbS
'Garnet Group'
Formula: X3Z2(SiO4)3
Goethite
Formula: Fe3+O(OH)
Gypsum
Formula: CaSO4 · 2H2O
Hematite
Formula: Fe2O3
Kaolinite
Formula: Al2(Si2O5)(OH)4
'K Feldspar'
'Limonite'
Magnetite
Formula: Fe2+Fe3+2O4
Molybdenite
Formula: MoS2
Muscovite
Formula: KAl2(AlSi3O10)(OH)2
Muscovite var. Sericite
Formula: KAl2(AlSi3O10)(OH)2
Native Copper
Formula: Cu
Phlogopite
Formula: KMg3(AlSi3O10)(OH)2
Description: Occurs in metadolomites with chondrodite and forsterite.
Pyrite
Formula: FeS2
Rutile
Formula: TiO2
'Smectite Group'
Formula: A0.3D2-3[T4O10]Z2 · nH2O
Sphalerite
Formula: ZnS
Tenorite
Formula: CuO
Tremolite
Formula: ◻Ca2Mg5(Si8O22)(OH)2
'Wad'

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
Native Copper1.AA.05Cu
Group 2 - Sulphides and Sulfosalts
Chalcocite2.BA.05Cu2S
Bornite2.BA.15Cu5FeS4
Covellite2.CA.05aCuS
Sphalerite2.CB.05aZnS
Chalcopyrite2.CB.10aCuFeS2
Galena2.CD.10PbS
Molybdenite2.EA.30MoS2
Pyrite2.EB.05aFeS2
Group 3 - Halides
Atacamite3.DA.10aCu2(OH)3Cl
Group 4 - Oxides and Hydroxides
Goethite4.00.Fe3+O(OH)
Cuprite4.AA.10Cu2O
Tenorite4.AB.10CuO
Magnetite4.BB.05Fe2+Fe3+2O4
Hematite4.CB.05Fe2O3
Rutile4.DB.05TiO2
Group 5 - Nitrates and Carbonates
Calcite5.AB.05CaCO3
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
Anhydrite7.AD.30CaSO4
Brochantite7.BB.25Cu4(SO4)(OH)6
Gypsum7.CD.40CaSO4 · 2H2O
Group 9 - Silicates
Forsterite9.AC.05Mg2SiO4
Chondrodite9.AF.45Mg5(SiO4)2F2
Dioptase9.CJ.30CuSiO3 · H2O
Diopside9.DA.15CaMgSi2O6
Tremolite9.DE.10◻Ca2Mg5(Si8O22)(OH)2
Muscovite9.EC.15KAl2(AlSi3O10)(OH)2
var. Sericite9.EC.15KAl2(AlSi3O10)(OH)2
Phlogopite9.EC.20KMg3(AlSi3O10)(OH)2
Kaolinite9.ED.05Al2(Si2O5)(OH)4
Chrysocolla9.ED.20Cu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Unclassified
'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
'Chlorite Group'-
'Limonite'-
'Wad'-
'K Feldspar'-
'Garnet Group'-X3Z2(SiO4)3
'Smectite Group'-A0.3D2-3[T4O10]Z2 · nH2O

List of minerals for each chemical element

HHydrogen
H AtacamiteCu2(OH)3Cl
H BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
H BrochantiteCu4(SO4)(OH)6
H ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
H DioptaseCuSiO3 · H2O
H GoethiteFe3+O(OH)
H GypsumCaSO4 · 2H2O
H KaoliniteAl2(Si2O5)(OH)4
H MuscoviteKAl2(AlSi3O10)(OH)2
H PhlogopiteKMg3(AlSi3O10)(OH)2
H Tremolite◻Ca2Mg5(Si8O22)(OH)2
H Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
H Smectite GroupA0.3D2-3[T4O10]Z2 · nH2O
CCarbon
C CalciteCaCO3
OOxygen
O AnhydriteCaSO4
O AtacamiteCu2(OH)3Cl
O BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
O BrochantiteCu4(SO4)(OH)6
O CalciteCaCO3
O ChondroditeMg5(SiO4)2F2
O ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
O CupriteCu2O
O DiopsideCaMgSi2O6
O DioptaseCuSiO3 · H2O
O ForsteriteMg2SiO4
O GoethiteFe3+O(OH)
O GypsumCaSO4 · 2H2O
O HematiteFe2O3
O KaoliniteAl2(Si2O5)(OH)4
O MagnetiteFe2+Fe23+O4
O MuscoviteKAl2(AlSi3O10)(OH)2
O PhlogopiteKMg3(AlSi3O10)(OH)2
O RutileTiO2
O TenoriteCuO
O Tremolite◻Ca2Mg5(Si8O22)(OH)2
O Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
O Garnet GroupX3Z2(SiO4)3
O Smectite GroupA0.3D2-3[T4O10]Z2 · nH2O
FFluorine
F BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
F ChondroditeMg5(SiO4)2F2
MgMagnesium
Mg BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Mg ChondroditeMg5(SiO4)2F2
Mg DiopsideCaMgSi2O6
Mg ForsteriteMg2SiO4
Mg PhlogopiteKMg3(AlSi3O10)(OH)2
Mg Tremolite◻Ca2Mg5(Si8O22)(OH)2
AlAluminium
Al BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Al ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Al KaoliniteAl2(Si2O5)(OH)4
Al MuscoviteKAl2(AlSi3O10)(OH)2
Al PhlogopiteKMg3(AlSi3O10)(OH)2
Al Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SiSilicon
Si BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Si ChondroditeMg5(SiO4)2F2
Si ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Si DiopsideCaMgSi2O6
Si DioptaseCuSiO3 · H2O
Si ForsteriteMg2SiO4
Si KaoliniteAl2(Si2O5)(OH)4
Si MuscoviteKAl2(AlSi3O10)(OH)2
Si PhlogopiteKMg3(AlSi3O10)(OH)2
Si Tremolite◻Ca2Mg5(Si8O22)(OH)2
Si Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Si Garnet GroupX3Z2(SiO4)3
SSulfur
S AnhydriteCaSO4
S BorniteCu5FeS4
S BrochantiteCu4(SO4)(OH)6
S ChalcopyriteCuFeS2
S ChalcociteCu2S
S CovelliteCuS
S GalenaPbS
S GypsumCaSO4 · 2H2O
S MolybdeniteMoS2
S PyriteFeS2
S SphaleriteZnS
ClChlorine
Cl AtacamiteCu2(OH)3Cl
KPotassium
K BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
K MuscoviteKAl2(AlSi3O10)(OH)2
K PhlogopiteKMg3(AlSi3O10)(OH)2
K Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CaCalcium
Ca AnhydriteCaSO4
Ca CalciteCaCO3
Ca DiopsideCaMgSi2O6
Ca GypsumCaSO4 · 2H2O
Ca Tremolite◻Ca2Mg5(Si8O22)(OH)2
TiTitanium
Ti BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Ti RutileTiO2
FeIron
Fe BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Fe BorniteCu5FeS4
Fe ChalcopyriteCuFeS2
Fe GoethiteFe3+O(OH)
Fe HematiteFe2O3
Fe MagnetiteFe2+Fe23+O4
Fe PyriteFeS2
CuCopper
Cu AtacamiteCu2(OH)3Cl
Cu BorniteCu5FeS4
Cu BrochantiteCu4(SO4)(OH)6
Cu ChalcopyriteCuFeS2
Cu ChalcociteCu2S
Cu ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O, x < 1
Cu CovelliteCuS
Cu CupriteCu2O
Cu Native CopperCu
Cu DioptaseCuSiO3 · H2O
Cu TenoriteCuO
ZnZinc
Zn SphaleriteZnS
MoMolybdenum
Mo MolybdeniteMoS2
PbLead
Pb GalenaPbS

Other Databases

Link to USGS MRDS:10106636

Other Regions, Features and Areas containing this locality

North America Plate
USA

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