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Questa Molybdenum Mine (Questa Mine; Moly Mine; R and S Mine), Questa, Taos County, New Mexico, USAi
Regional Level Types
Questa Molybdenum Mine (Questa Mine; Moly Mine; R and S Mine)Mine
QuestaVillage
Taos CountyCounty
New MexicoState
USACountry

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PhotosMapsSearch
07318530017272023406765.jpg
Molybdenite

Questa Molybdenum Mine, Questa, Taos County, New Mexico, USA
09472660017272014734685.jpg
Ferrimolybdite

Questa Molybdenum Mine, Questa, Taos County, New Mexico, USA
03833290017272045365881.jpg
Ferrimolybdite, etc.

Questa Molybdenum Mine, Questa, Taos County, New Mexico, USA
07318530017272023406765.jpg
Molybdenite

Questa Molybdenum Mine, Questa, Taos County, New Mexico, USA
05598590017272045388899.jpg
Ferrimolybdite

Questa Molybdenum Mine, Questa, Taos County, New Mexico, USA
03833290017272045365881.jpg
Ferrimolybdite, etc.

Questa Molybdenum Mine, Questa, Taos County, New Mexico, USA
07318530017272023406765.jpg
Molybdenite

Questa Molybdenum Mine, Questa, Taos County, New Mexico, USA
09472660017272014734685.jpg
Ferrimolybdite

Questa Molybdenum Mine, Questa, Taos County, New Mexico, USA
Latitude & Longitude (WGS84):
36° 42' 15'' North , 105° 30' 23'' West
Latitude & Longitude (decimal):
36.70417,-105.50639
GRN:
N25W61
Type:
Mine
Köppen climate type:
Dfb : Warm-summer humid continental climate
Nearest Settlements:
PlacePopulationDistance
Questa1,753 (2017)7.9km
Red River476 (2017)8.9km
San Cristobal273 (2011)16.9km
Arroyo Seco1,785 (2011)21.6km
Arroyo Hondo474 (2011)23.7km
Mindat Locality ID:
19266
Long-form identifier:
mindat:1:2:19266:9
GUID (UUID V4):
0


A molybdenum-rhenium mine owned by Molycorp, a subsidiary of Unocal Corp. Produced 4,760 tons of Mo in concentrates (1984). In 2011, the mine was declared a superfund site - on June 2, 2014 the mine was declared permanently closed.

Located nine miles from Questa, the mine opened in 1916 as the R&S Molybdenum mine. It was purchased by Molycorp Minerals in 1950 and became a subsidiary of Chevron in 2005. Formerly an open pit excavation, the Chevron Questa mine had operated as an underground mine since 1982.
Deposit: Underground mine being developed for 1983 production.mine shut in 1986.plans to reopen 2nd qtr 1989 with initial production at half-capacity, annual rate 10-12 mm lbs mo/yr.resumed operations adit reserve data As in-situ. (mo recovery is 87%) geology property reviewed by rc smith, 4-87. At this time, the mine is temporarily shutdown . Closed since feb. 1986. Q4 matrix was added for the new reserve estimate because of the complex q data from the 1979 evaluation. Molycorp expects to re-open mine by 3rd qu-96, depending on permitting progress. See ref "mi" 001-002. Molycorp began installing pumping equipment for possible reopening in july of 1996. (at 14-15 mil lb/yr moly cont.)

Geology: Lithology the ore horizon appears to be concentrated at the contact between the intrusives (consisting of monzonite, granite, rhyolite and aplite porphyries) and the underlying extrusives (consisting of tuffs, latites, breccias, rhyolites and andesites). The questa ore deposit is two segments, each segment is a part of two flat-lying , elongated and paralell mineralized zones. These zones strike N 70 deg. W and are structurally-controlled by two fault systems that form a graben-like structure (?). The N E zone is exposed in the pit and extends in a northwesterly direction for 1600 m. The portion that is ore grade (called the f-2 ore zone) is 125 m wide and 125 m thick. The s W zone lies 1800 meters southeast of NE zone. This ore deposit is approximately 1600 meters long, 180 meters wide, and 120 meters thick.

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


28 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:

ⓘ Alunite
Formula: KAl3(SO4)2(OH)6
ⓘ 'Apatite'
Formula: Ca5(PO4)3(Cl/F/OH)
ⓘ Beryl
Formula: Be3Al2(Si6O18)
ⓘ 'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ Calcite
Formula: CaCO3
ⓘ Chalcopyrite
Formula: CuFeS2
ⓘ 'Chlorite Group'
ⓘ Epidote
Formula: (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘ Ferrimolybdite
Formula: Fe2(MoO4)3 · nH2O
ⓘ Fluorite
Formula: CaF2
ⓘ Galena
Formula: PbS
ⓘ Graphite
Formula: C
ⓘ Gypsum
Formula: CaSO4 · 2H2O
ⓘ Hematite
Formula: Fe2O3
ⓘ Hübnerite
Formula: MnWO4
ⓘ Jarosite
Formula: KFe3+3(SO4)2(OH)6
ⓘ Kaolinite
Formula: Al2(Si2O5)(OH)4
ⓘ 'K Feldspar'
ⓘ 'K Feldspar var. Adularia'
Formula: KAlSi3O8
ⓘ 'Limonite'
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
ⓘ Malachite
Formula: Cu2(CO3)(OH)2
ⓘ Molybdenite
Formula: MoS2
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Muscovite var. Illite
Formula: K0.65Al2.0[Al0.65Si3.35O10](OH)2
ⓘ Muscovite var. Sericite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Orthoclase
Formula: K(AlSi3O8)
ⓘ Pyrite
Formula: FeS2
ⓘ Quartz
Formula: SiO2
ⓘ Rhodochrosite
Formula: MnCO3
ⓘ Rhodonite ?
Formula: CaMn3Mn[Si5O15]
ⓘ Rutile
Formula: TiO2
ⓘ Scheelite
Formula: Ca(WO4)
ⓘ Sphalerite
Formula: ZnS
ⓘ Topaz
Formula: Al2(SiO4)(F,OH)2
ⓘ 'Wad'
ⓘ Zircon
Formula: Zr(SiO4)

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘGraphite1.CB.05aC
Group 2 - Sulphides and Sulfosalts
ⓘSphalerite2.CB.05aZnS
ⓘChalcopyrite2.CB.10aCuFeS2
ⓘGalena2.CD.10PbS
ⓘMolybdenite2.EA.30MoS2
ⓘPyrite2.EB.05aFeS2
Group 3 - Halides
ⓘFluorite3.AB.25CaF2
Group 4 - Oxides and Hydroxides
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘHematite4.CB.05Fe2O3
ⓘQuartz4.DA.05SiO2
ⓘRutile4.DB.05TiO2
ⓘHübnerite4.DB.30MnWO4
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
ⓘRhodochrosite5.AB.05MnCO3
ⓘMalachite5.BA.10Cu2(CO3)(OH)2
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘAlunite7.BC.10KAl3(SO4)2(OH)6
ⓘJarosite7.BC.10KFe3+3(SO4)2(OH)6
ⓘGypsum7.CD.40CaSO4 · 2H2O
ⓘScheelite7.GA.05Ca(WO4)
ⓘFerrimolybdite7.GB.30Fe2(MoO4)3 · nH2O
Group 9 - Silicates
ⓘZircon9.AD.30Zr(SiO4)
ⓘTopaz9.AF.35Al2(SiO4)(F,OH)2
ⓘEpidote9.BG.05a(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘBeryl9.CJ.05Be3Al2(Si6O18)
ⓘRhodonite ?9.DK.05CaMn3Mn[Si5O15]
ⓘMuscovite
var. Illite		9.EC.15K0.65Al2.0[Al0.65Si3.35O10](OH)2
ⓘ9.EC.15KAl2(AlSi3O10)(OH)2
ⓘvar. Sericite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘKaolinite9.ED.05Al2(Si2O5)(OH)4
ⓘOrthoclase9.FA.30K(AlSi3O8)
Unclassified
ⓘ'K Feldspar
var. Adularia'		-KAlSi3O8
ⓘ'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ'Chlorite Group'-
ⓘ'Limonite'-
ⓘ'Wad'-
ⓘ'K Feldspar'-
ⓘ'Apatite'-Ca5(PO4)3(Cl/F/OH)

List of minerals for each chemical element

HHydrogen
Hⓘ AluniteKAl3(SO4)2(OH)6
Hⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Hⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Hⓘ FerrimolybditeFe2(MoO4)3 · nH2O
Hⓘ GypsumCaSO4 · 2H2O
Hⓘ Muscovite var. IlliteK0.65Al2.0[Al0.65Si3.35O10](OH)2
Hⓘ JarositeKFe33+(SO4)2(OH)6
Hⓘ KaoliniteAl2(Si2O5)(OH)4
Hⓘ MalachiteCu2(CO3)(OH)2
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ TopazAl2(SiO4)(F,OH)2
Hⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Hⓘ ApatiteCa5(PO4)3(Cl/F/OH)
BeBeryllium
Beⓘ BerylBe3Al2(Si6O18)
CCarbon
Cⓘ CalciteCaCO3
Cⓘ GraphiteC
Cⓘ MalachiteCu2(CO3)(OH)2
Cⓘ RhodochrositeMnCO3
OOxygen
Oⓘ K Feldspar var. AdulariaKAlSi3O8
Oⓘ AluniteKAl3(SO4)2(OH)6
Oⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Oⓘ BerylBe3Al2(Si6O18)
Oⓘ CalciteCaCO3
Oⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Oⓘ FerrimolybditeFe2(MoO4)3 · nH2O
Oⓘ GypsumCaSO4 · 2H2O
Oⓘ HematiteFe2O3
Oⓘ HübneriteMnWO4
Oⓘ Muscovite var. IlliteK0.65Al2.0[Al0.65Si3.35O10](OH)2
Oⓘ JarositeKFe33+(SO4)2(OH)6
Oⓘ KaoliniteAl2(Si2O5)(OH)4
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ MalachiteCu2(CO3)(OH)2
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ OrthoclaseK(AlSi3O8)
Oⓘ QuartzSiO2
Oⓘ RhodochrositeMnCO3
Oⓘ RhodoniteCaMn3Mn[Si5O15]
Oⓘ RutileTiO2
Oⓘ ScheeliteCa(WO4)
Oⓘ TopazAl2(SiO4)(F,OH)2
Oⓘ ZirconZr(SiO4)
Oⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Oⓘ ApatiteCa5(PO4)3(Cl/F/OH)
FFluorine
Fⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Fⓘ FluoriteCaF2
Fⓘ TopazAl2(SiO4)(F,OH)2
Fⓘ ApatiteCa5(PO4)3(Cl/F/OH)
MgMagnesium
Mgⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
AlAluminium
Alⓘ K Feldspar var. AdulariaKAlSi3O8
Alⓘ AluniteKAl3(SO4)2(OH)6
Alⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Alⓘ BerylBe3Al2(Si6O18)
Alⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Alⓘ Muscovite var. IlliteK0.65Al2.0[Al0.65Si3.35O10](OH)2
Alⓘ KaoliniteAl2(Si2O5)(OH)4
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ OrthoclaseK(AlSi3O8)
Alⓘ TopazAl2(SiO4)(F,OH)2
Alⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SiSilicon
Siⓘ K Feldspar var. AdulariaKAlSi3O8
Siⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Siⓘ BerylBe3Al2(Si6O18)
Siⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Siⓘ Muscovite var. IlliteK0.65Al2.0[Al0.65Si3.35O10](OH)2
Siⓘ KaoliniteAl2(Si2O5)(OH)4
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ OrthoclaseK(AlSi3O8)
Siⓘ QuartzSiO2
Siⓘ RhodoniteCaMn3Mn[Si5O15]
Siⓘ TopazAl2(SiO4)(F,OH)2
Siⓘ ZirconZr(SiO4)
Siⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
PPhosphorus
Pⓘ ApatiteCa5(PO4)3(Cl/F/OH)
SSulfur
Sⓘ AluniteKAl3(SO4)2(OH)6
Sⓘ ChalcopyriteCuFeS2
Sⓘ GalenaPbS
Sⓘ GypsumCaSO4 · 2H2O
Sⓘ JarositeKFe33+(SO4)2(OH)6
Sⓘ MolybdeniteMoS2
Sⓘ PyriteFeS2
Sⓘ SphaleriteZnS
ClChlorine
Clⓘ ApatiteCa5(PO4)3(Cl/F/OH)
KPotassium
Kⓘ K Feldspar var. AdulariaKAlSi3O8
Kⓘ AluniteKAl3(SO4)2(OH)6
Kⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Kⓘ Muscovite var. IlliteK0.65Al2.0[Al0.65Si3.35O10](OH)2
Kⓘ JarositeKFe33+(SO4)2(OH)6
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Kⓘ OrthoclaseK(AlSi3O8)
Kⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CaCalcium
Caⓘ CalciteCaCO3
Caⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Caⓘ FluoriteCaF2
Caⓘ GypsumCaSO4 · 2H2O
Caⓘ RhodoniteCaMn3Mn[Si5O15]
Caⓘ ScheeliteCa(WO4)
Caⓘ ApatiteCa5(PO4)3(Cl/F/OH)
TiTitanium
Tiⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Tiⓘ RutileTiO2
MnManganese
Mnⓘ HübneriteMnWO4
Mnⓘ RhodochrositeMnCO3
Mnⓘ RhodoniteCaMn3Mn[Si5O15]
FeIron
Feⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Feⓘ ChalcopyriteCuFeS2
Feⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Feⓘ FerrimolybditeFe2(MoO4)3 · nH2O
Feⓘ HematiteFe2O3
Feⓘ JarositeKFe33+(SO4)2(OH)6
Feⓘ MagnetiteFe2+Fe23+O4
Feⓘ PyriteFeS2
CuCopper
Cuⓘ ChalcopyriteCuFeS2
Cuⓘ MalachiteCu2(CO3)(OH)2
ZnZinc
Znⓘ SphaleriteZnS
ZrZirconium
Zrⓘ ZirconZr(SiO4)
MoMolybdenum
Moⓘ FerrimolybditeFe2(MoO4)3 · nH2O
Moⓘ MolybdeniteMoS2
WTungsten
Wⓘ HübneriteMnWO4
Wⓘ ScheeliteCa(WO4)
PbLead
Pbⓘ GalenaPbS

Other Databases

Link to USGS MRDS:10198817

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

Schilling, John H. (1956) Geology of the Questa Molybdenum (Moly) mine area, Taos County, New Mexico. Bulletin 51. New Mexico Bureau of Geology and Mineral Resources doi:10.58799/b-51
Clark, K. F. and C. B. Read (1972), Geology and Ore Deposits of Eagle Nest area, New Mexico. New Mexico Bureau of Geology and Mineral Resources Bulletin 94.
Mining Annual Review(1985):118 & 331.
Cline, Jean S. & Bodnar, Robert J. (1994): Direct evolution of brine from a crystallizing silicic melt at the Questa, New Mexico, molybdenum deposit. Economic Geology 89, 1780-1802.
RYAN'S NOTES, NEWS, FEB. 13, (1995), "CLIMAX MOLY TO OPEN
Northrop, Stuart A., LaBruzza, F.A. (1996) Minerals of New Mexico (3rd ed.) University of New Mexico Press, Albuquerque, NM.
en.wikipedia.org (2005) http://en.wikipedia.org/wiki/Questa,_New_Mexico
Campbell, A.R., and Lueth, V.W. (2008): Isotopic and textural discrimination between hypogene, ancient supergene, and modern sulfates at the Questa Mine, New Mexico. Applied Geochemistry 23, 308-319.
Junxing Zhao, Kezhang Qin, Guangming Li, and Jinxiang Li (2011): Characteristics of alteration and mineralization in the Sharang porphyry molybdenum deposit in the northern margin of Gangdese and comparison with typical porphyry molybdenum deposits in the world. Geology and Exploration 47(1), 54-70.
DeMark, Ramon S. (2015): Minerals of the Questa Moly Mine, Taos County, New Mexico. 36th Annual New Mexico Mineral Symposium Program & Abstracts, page 9.
Gaynor, Sean P., Rosera, Joshua M., Coleman, Drew S. (2023) Genesis of the Questa Mo Porphyry Deposit and Nearby Polymetallic Mineralization, New Mexico, USA. Economic Geology, 118 (6) 1319-1339 doi:10.5382/econgeo.5011
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