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Both zinc ore Sphalerite and calcium plagioclase feldspar Anorthite have perfect cleavage that will split cleanly if you hit them with a hammer, but only one can claim a larger split of your votes!
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Gem Mine, Gem Park complex, Fremont County, Colorado, USAi
Regional Level Types
Gem MineMine
Gem Park complexComplex
Fremont CountyCounty
ColoradoState
USACountry

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Latitude & Longitude (WGS84):
38° 16' 30'' North , 105° 32' 46'' West
Latitude & Longitude (decimal):
38.27526,-105.54617
GeoHash:
G#: 9wucwpz9e
GRN:
N26W60
Type:
Mine
Köppen climate type:
BSk : Cold semi-arid (steppe) climate
Nearest Settlements:
PlacePopulationDistance
Westcliffe577 (2017)17.1km
Silver Cliff591 (2017)17.8km
Coaldale255 (2011)21.0km
Howard723 (2011)31.7km
Cañon City16,400 (2013)32.2km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Canon City Geology ClubCanon City, Colorado32km
Columbine Gem and Mineral SocietySalida, Colorado49km
Mindat Locality ID:
6203
Long-form identifier:
mindat:1:2:6203:2
GUID (UUID V4):
0


Ref.: Eckel, Edwin B. (1997), Minerals of Colorado, updated & revised: 16. This old mine, known since Cross (1884), is near the valley floor on the southern slopes of Gem Mountain on the North side of Gem Park (N ½ sec. 33, T. 47 S., R. 73 W.).

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


12 valid minerals.

Detailed Mineral List:

ⓘ 'Ancylite'
ⓘ Annabergite
Formula: Ni3(AsO4)2 · 8H2O
ⓘ Baryte
Formula: BaSO4
ⓘ Bornite
Formula: Cu5FeS4
ⓘ Calcite
Formula: CaCO3
ⓘ Chalcocite
Formula: Cu2S
ⓘ Chalcopyrite
Formula: CuFeS2
ⓘ Maucherite
Formula: Ni11As8
ⓘ 'Monazite Group'
Formula: REE(PO4)
ⓘ Native Silver ?
Formula: Ag
ⓘ Nickeline
Formula: NiAs
ⓘ Phlogopite
Formula: KMg3(AlSi3O10)(OH)2
ⓘ Pyrite
Formula: FeS2
ⓘ Quartz
Formula: SiO2

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘNative Silver ?1.AA.05Ag
Group 2 - Sulphides and Sulfosalts
ⓘMaucherite2.AB.15Ni11As8
ⓘChalcocite2.BA.05Cu2S
ⓘBornite2.BA.15Cu5FeS4
ⓘChalcopyrite2.CB.10aCuFeS2
ⓘNickeline2.CC.05NiAs
ⓘPyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
ⓘQuartz4.DA.05SiO2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘBaryte7.AD.35BaSO4
Group 8 - Phosphates, Arsenates and Vanadates
ⓘAnnabergite8.CE.40Ni3(AsO4)2 · 8H2O
Group 9 - Silicates
ⓘPhlogopite9.EC.20KMg3(AlSi3O10)(OH)2
Unclassified
ⓘ'Monazite Group'-REE(PO4)
ⓘ'Ancylite'-

List of minerals for each chemical element

HHydrogen
Hⓘ AnnabergiteNi3(AsO4)2 · 8H2O
Hⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
CCarbon
Cⓘ CalciteCaCO3
OOxygen
Oⓘ AnnabergiteNi3(AsO4)2 · 8H2O
Oⓘ BaryteBaSO4
Oⓘ CalciteCaCO3
Oⓘ Monazite GroupREE(PO4)
Oⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Oⓘ QuartzSiO2
MgMagnesium
Mgⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
AlAluminium
Alⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
SiSilicon
Siⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
Siⓘ QuartzSiO2
PPhosphorus
Pⓘ Monazite GroupREE(PO4)
SSulfur
Sⓘ BaryteBaSO4
Sⓘ BorniteCu5FeS4
Sⓘ ChalcopyriteCuFeS2
Sⓘ ChalcociteCu2S
Sⓘ PyriteFeS2
KPotassium
Kⓘ PhlogopiteKMg3(AlSi3O10)(OH)2
CaCalcium
Caⓘ CalciteCaCO3
FeIron
Feⓘ BorniteCu5FeS4
Feⓘ ChalcopyriteCuFeS2
Feⓘ PyriteFeS2
NiNickel
Niⓘ AnnabergiteNi3(AsO4)2 · 8H2O
Niⓘ MaucheriteNi11As8
Niⓘ NickelineNiAs
CuCopper
Cuⓘ BorniteCu5FeS4
Cuⓘ ChalcopyriteCuFeS2
Cuⓘ ChalcociteCu2S
AsArsenic
Asⓘ AnnabergiteNi3(AsO4)2 · 8H2O
Asⓘ MaucheriteNi11As8
Asⓘ NickelineNiAs
AgSilver
Agⓘ Native SilverAg
BaBarium
Baⓘ BaryteBaSO4

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

Armbrustmacher, T. J. (1988) Geology and resources of thorium and associated elements in the Wet Mountains area, Fremont and Custer counties, Colorado. USGS Professional Paper: 1049-F
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