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Cotopaxi Feldspar Mine (Cotopaxi Feldspar prospect; Henry pegmatite), Cotopaxi Pegmatite area, Cotopaxi, Cotopaxi Mining District, Fremont County, Colorado, USAi
Regional Level Types
Cotopaxi Feldspar Mine (Cotopaxi Feldspar prospect; Henry pegmatite)Mine
Cotopaxi Pegmatite areaArea
Cotopaxi- not defined -
Cotopaxi Mining DistrictMining District
Fremont CountyCounty
ColoradoState
USACountry

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Latitude & Longitude (WGS84):
38° 25' 11'' North , 105° 40' 27'' West
Latitude & Longitude (decimal):
Type:
Nearest Settlements:
PlacePopulationDistance
Coaldale255 (2011)9.5km
Howard723 (2011)14.4km
Salida5,467 (2017)31.0km
Smeltertown120 (2011)32.8km
Westcliffe577 (2017)36.5km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Columbine Gem and Mineral SocietySalida, Colorado31km
Canon City Geology ClubCanon City, Colorado38km
Mindat Locality ID:
6116
Long-form identifier:
mindat:1:2:6116:5
GUID (UUID V4):
0


A former feldspar pegmatite occurrence/mine located on the boundary between secs. 7 & 8, T48N, R12E, NMM, approximately 3½ miles NNE of Cotopaxi, W of Fernleaf Gulch, E of Bernard Creek and N of the Arkansas River. Owned by the Colorado Feldspar Company, Canon City. Operated for several months in 1939.

NOTE: The geographic coordinates presented were taken from the topo map based on the description furnished (prospect on the secs. 7 & 8 line).

The pegmatite cropped out as an irregular knob prior to mining, but this knob has been almost completely removed. The exposures that remain consist of graphic and granitic intergrowths of quartz and feldspar, massive quartz, nests of biotite, and distorted octahedrons of magnetite. A small quantity of buff to gray feldspar occurs in masses 2 feet in length. After crystallization of the feldspar, it was altered by solutions, and hematite, muscovite, uraninite, and another mineral tentatively identified as samarskite were deposited. One patch of pegmatite containing 75 pounds of uraninite is reported to have been found.

Workings include a shallow open cut 60 feet long, 40 feet wide and 6 feet deep (the topo map reflects 1 prospect pit symbol at the end of a unimproved, dead end road).

A few hundred tons of feldspar were produced.

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. 1 erroneous literature entry.

Detailed Mineral List:

Allanite-(Ce)
Formula: (CaCe)(AlAlFe2+)O[Si2O7][SiO4](OH)
'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
'Columbite-(Fe)-Columbite-(Mn) Series'
Euxenite-(Y)
Formula: (Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
Fluorite
Formula: CaF2
Hematite
Formula: Fe2O3
'Hornblende Root Name Group'
Formula: ◻Ca2(Z2+4Z3+)(AlSi7O22)(OH,F,Cl)2
Kainosite-(Y)
Formula: Ca2Y2(SiO3)4(CO3) · H2O
Magnetite
Formula: Fe2+Fe3+2O4
Microcline
Formula: K(AlSi3O8)
Monazite-(Ce)
Formula: Ce(PO4)
Description: Reidentified as crytolite
Muscovite
Formula: KAl2(AlSi3O10)(OH)2
'Plagioclase'
Formula: (Na,Ca)[(Si,Al)AlSi2]O8
Quartz
Formula: SiO2
Samarskite-(Y)
Formula: YFe3+Nb2O8
Synchysite-(Y)
Formula: CaY(CO3)2F
Uraninite
Formula: UO2
Xenotime-(Y)
Formula: Y(PO4)
Zircon
Formula: Zr(SiO4)
Zircon var. Cyrtolite
Formula: Zr[(SiO4),(OH)4]

List of minerals arranged by Strunz 10th Edition classification

Group 3 - Halides
Fluorite3.AB.25CaF2
Group 4 - Oxides and Hydroxides
Magnetite4.BB.05Fe2+Fe3+2O4
Hematite4.CB.05Fe2O3
Quartz4.DA.05SiO2
Samarskite-(Y)4.DB.25YFe3+Nb2O8
Euxenite-(Y)4.DG.05(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
Uraninite4.DL.05UO2
Group 5 - Nitrates and Carbonates
Synchysite-(Y)5.BD.20cCaY(CO3)2F
Group 8 - Phosphates, Arsenates and Vanadates
Xenotime-(Y)8.AD.35Y(PO4)
Monazite-(Ce) ?8.AD.50Ce(PO4)
Group 9 - Silicates
Zircon9.AD.30Zr(SiO4)
var. Cyrtolite9.AD.30Zr[(SiO4),(OH)4]
Allanite-(Ce)9.BG.05b(CaCe)(AlAlFe2+)O[Si2O7][SiO4](OH)
Kainosite-(Y)9.CF.10Ca2Y2(SiO3)4(CO3) · H2O
Muscovite9.EC.15KAl2(AlSi3O10)(OH)2
Microcline9.FA.30K(AlSi3O8)
Unclassified
'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
'Columbite-(Fe)-Columbite-(Mn) Series'-
'Hornblende Root Name Group'-◻Ca2(Z2+4Z3+)(AlSi7O22)(OH,F,Cl)2
'Plagioclase'-(Na,Ca)[(Si,Al)AlSi2]O8

List of minerals for each chemical element

HHydrogen
H Allanite-(Ce)(CaCe)(AlAlFe2+)O[Si2O7][SiO4](OH)
H BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
H Kainosite-(Y)Ca2Y2(SiO3)4(CO3) · H2O
H MuscoviteKAl2(AlSi3O10)(OH)2
H Zircon var. CyrtoliteZr[(SiO4),(OH)4]
H Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
CCarbon
C Kainosite-(Y)Ca2Y2(SiO3)4(CO3) · H2O
C Synchysite-(Y)CaY(CO3)2F
OOxygen
O Allanite-(Ce)(CaCe)(AlAlFe2+)O[Si2O7][SiO4](OH)
O BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
O Euxenite-(Y)(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
O HematiteFe2O3
O Kainosite-(Y)Ca2Y2(SiO3)4(CO3) · H2O
O MagnetiteFe2+Fe23+O4
O MicroclineK(AlSi3O8)
O Monazite-(Ce)Ce(PO4)
O MuscoviteKAl2(AlSi3O10)(OH)2
O QuartzSiO2
O Samarskite-(Y)YFe3+Nb2O8
O Synchysite-(Y)CaY(CO3)2F
O UraniniteUO2
O Xenotime-(Y)Y(PO4)
O ZirconZr(SiO4)
O Zircon var. CyrtoliteZr[(SiO4),(OH)4]
O Columbite-(Fe)-Columbite-(Mn) Series
O Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
O Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
FFluorine
F BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
F FluoriteCaF2
F Synchysite-(Y)CaY(CO3)2F
F Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
NaSodium
Na Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
MgMagnesium
Mg BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
AlAluminium
Al Allanite-(Ce)(CaCe)(AlAlFe2+)O[Si2O7][SiO4](OH)
Al BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Al MicroclineK(AlSi3O8)
Al MuscoviteKAl2(AlSi3O10)(OH)2
Al Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
Al Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
SiSilicon
Si Allanite-(Ce)(CaCe)(AlAlFe2+)O[Si2O7][SiO4](OH)
Si BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Si Kainosite-(Y)Ca2Y2(SiO3)4(CO3) · H2O
Si MicroclineK(AlSi3O8)
Si MuscoviteKAl2(AlSi3O10)(OH)2
Si QuartzSiO2
Si ZirconZr(SiO4)
Si Zircon var. CyrtoliteZr[(SiO4),(OH)4]
Si Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
Si Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
PPhosphorus
P Monazite-(Ce)Ce(PO4)
P Xenotime-(Y)Y(PO4)
ClChlorine
Cl Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
KPotassium
K BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
K MicroclineK(AlSi3O8)
K MuscoviteKAl2(AlSi3O10)(OH)2
CaCalcium
Ca Allanite-(Ce)(CaCe)(AlAlFe2+)O[Si2O7][SiO4](OH)
Ca Euxenite-(Y)(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
Ca FluoriteCaF2
Ca Kainosite-(Y)Ca2Y2(SiO3)4(CO3) · H2O
Ca Synchysite-(Y)CaY(CO3)2F
Ca Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
Ca Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
TiTitanium
Ti BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Ti Euxenite-(Y)(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
MnManganese
Mn Columbite-(Fe)-Columbite-(Mn) Series
FeIron
Fe Allanite-(Ce)(CaCe)(AlAlFe2+)O[Si2O7][SiO4](OH)
Fe BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Fe HematiteFe2O3
Fe MagnetiteFe2+Fe23+O4
Fe Samarskite-(Y)YFe3+Nb2O8
Fe Columbite-(Fe)-Columbite-(Mn) Series
YYttrium
Y Euxenite-(Y)(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
Y Kainosite-(Y)Ca2Y2(SiO3)4(CO3) · H2O
Y Samarskite-(Y)YFe3+Nb2O8
Y Synchysite-(Y)CaY(CO3)2F
Y Xenotime-(Y)Y(PO4)
ZrZirconium
Zr ZirconZr(SiO4)
Zr Zircon var. CyrtoliteZr[(SiO4),(OH)4]
NbNiobium
Nb Euxenite-(Y)(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
Nb Samarskite-(Y)YFe3+Nb2O8
Nb Columbite-(Fe)-Columbite-(Mn) Series
CeCerium
Ce Allanite-(Ce)(CaCe)(AlAlFe2+)O[Si2O7][SiO4](OH)
Ce Euxenite-(Y)(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
Ce Monazite-(Ce)Ce(PO4)
TaTantalum
Ta Euxenite-(Y)(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
ThThorium
Th Euxenite-(Y)(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
UUranium
U Euxenite-(Y)(Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6
U UraniniteUO2

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