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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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Duncan Mine, South Pass City, South Pass-Atlantic City Mining District, Fremont County, Wyoming, USAi
Regional Level Types
Duncan MineMine
South Pass CityUnincorporated Community
South Pass-Atlantic City Mining DistrictMining District
Fremont CountyCounty
WyomingState
USACountry

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PhotosMapsSearch
00267690017272025413992.jpg
Duncan Mine & Mill, 2017

Duncan Mine, South Pass City, South Pass-Atlantic City Mining District, Fremont County, Wyoming, USA
00267690017272025413992.jpg
Duncan Mine & Mill, 2017

Duncan Mine, South Pass City, South Pass-Atlantic City Mining District, Fremont County, Wyoming, USA
00267690017272025413992.jpg
Duncan Mine & Mill, 2017

Duncan Mine, South Pass City, South Pass-Atlantic City Mining District, Fremont County, Wyoming, USA
Latitude & Longitude (WGS84):
42° 29' 13'' North , 108° 45' 19'' West
Latitude & Longitude (decimal):
42.48722,-108.75528
GeoHash:
G#: 9xd9tnwcf
GRN:
N29W58
Type:
Mine
Köppen climate type:
Dfb : Warm-summer humid continental climate
Nearest Settlements:
PlacePopulationDistance
Lander7,686 (2017)38.5km
Boulder Flats408 (2011)47.4km
Hudson456 (2017)48.6km
Arapahoe1,656 (2011)57.1km
Mindat Locality ID:
7453
Long-form identifier:
mindat:1:2:7453:0
GUID (UUID V4):
0


A gold mine started in 1868.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


5 valid minerals.

Detailed Mineral List:

ⓘ Actinolite
Formula: ◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Muscovite var. Sericite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Native Gold
Formula: Au
ⓘ Native Silver
Formula: Ag
ⓘ Quartz
Formula: SiO2

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘNative Gold1.AA.05Au
ⓘNative Silver1.AA.05Ag
Group 4 - Oxides and Hydroxides
ⓘQuartz4.DA.05SiO2
Group 9 - Silicates
ⓘActinolite9.DE.10◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘvar. Sericite9.EC.15KAl2(AlSi3O10)(OH)2

List of minerals for each chemical element

HHydrogen
Hⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
OOxygen
Oⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ QuartzSiO2
Oⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
MgMagnesium
Mgⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
AlAluminium
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SiSilicon
Siⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ QuartzSiO2
Siⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
KPotassium
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Kⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CaCalcium
Caⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
FeIron
Feⓘ Actinolite◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2
AgSilver
Agⓘ Native SilverAg
AuGold
Auⓘ Native GoldAu

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate

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

Rocks & Min.:11:219 & 76:391.
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