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Eldora, Caribou Mining District, Boulder County, Colorado, USAi
Regional Level Types
EldoraTown
Caribou Mining DistrictMining District
Boulder CountyCounty
ColoradoState
USACountry

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Type:
Town
Mindat Locality ID:
159109
Long-form identifier:
mindat:1:2:159109:8
GUID (UUID V4):
0
Other/historical names associated with this locality:
Eldorado


Eldora is a town in the Caribou Mining District, about 3 miles west of Nederland. Local mines include the mines near Lost Lake and southwest of Grand Island as well as those south of the town. It has had only a small output and is of interest chiefly because of its gold-telluride ores, which were discovered about 1896. The deposits were actively developed during the following decade, but since 1906 the camp has been comparatively inactive. The only mine credited with a noteworthy output is the Enterprise, about half a mile south of Eldora.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded from this region.


Mineral List

Mineral list contains entries from the region specified including sub-localities

9 valid minerals.

Detailed Mineral List:

ⓘ Baryte
Formula: BaSO4
ⓘ 'K Feldspar'
ⓘ 'K Feldspar var. Adularia'
Formula: KAlSi3O8
ⓘ Molybdenite
Formula: MoS2
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Muscovite var. Sericite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Native Gold
Formula: Au
ⓘ Petzite
Formula: Ag3AuTe2
ⓘ Pyrite
Formula: FeS2
ⓘ Quartz
Formula: SiO2
ⓘ Roscoelite
Formula: KV3+2(AlSi3O10)(OH)2
ⓘ Sylvanite
Formula: AgAuTe4

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘNative Gold1.AA.05Au
Group 2 - Sulphides and Sulfosalts
ⓘPetzite2.BA.75Ag3AuTe2
ⓘSylvanite2.EA.05AgAuTe4
ⓘMolybdenite2.EA.30MoS2
ⓘPyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
ⓘQuartz4.DA.05SiO2
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘBaryte7.AD.35BaSO4
Group 9 - Silicates
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘRoscoelite9.EC.15KV3+2(AlSi3O10)(OH)2
ⓘMuscovite
var. Sericite		9.EC.15KAl2(AlSi3O10)(OH)2
Unclassified
ⓘ'K Feldspar
var. Adularia'		-KAlSi3O8
ⓘ''-

List of minerals for each chemical element

HHydrogen
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ RoscoeliteKV23+(AlSi3O10)(OH)2
Hⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
OOxygen
Oⓘ K Feldspar var. AdulariaKAlSi3O8
Oⓘ BaryteBaSO4
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ QuartzSiO2
Oⓘ RoscoeliteKV23+(AlSi3O10)(OH)2
Oⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
AlAluminium
Alⓘ K Feldspar var. AdulariaKAlSi3O8
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ RoscoeliteKV23+(AlSi3O10)(OH)2
Alⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SiSilicon
Siⓘ K Feldspar var. AdulariaKAlSi3O8
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ QuartzSiO2
Siⓘ RoscoeliteKV23+(AlSi3O10)(OH)2
Siⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SSulfur
Sⓘ BaryteBaSO4
Sⓘ MolybdeniteMoS2
Sⓘ PyriteFeS2
KPotassium
Kⓘ K Feldspar var. AdulariaKAlSi3O8
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Kⓘ RoscoeliteKV23+(AlSi3O10)(OH)2
Kⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
VVanadium
Vⓘ RoscoeliteKV23+(AlSi3O10)(OH)2
FeIron
Feⓘ PyriteFeS2
MoMolybdenum
Moⓘ MolybdeniteMoS2
AgSilver
Agⓘ PetziteAg3AuTe2
Agⓘ SylvaniteAgAuTe4
TeTellurium
Teⓘ PetziteAg3AuTe2
Teⓘ SylvaniteAgAuTe4
BaBarium
Baⓘ BaryteBaSO4
AuGold
Auⓘ Native GoldAu
Auⓘ PetziteAg3AuTe2
Auⓘ SylvaniteAgAuTe4

Fossils

This region is too big or complex to display the fossil list, try looking at smaller subregions.

Localities in this Region

USA

Other Regions, Features and Areas that Intersect

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

US Board on Geographic Names (n.d.) https://geonames.usgs.gov/apex/f?p=138:3:0::NO:3:P3_FID,P3_TITLE:181070,Eldora
Bastin, Edson S. and Hill, James M. (1917), Economic Geology of Gilpin County and adjacent parts of Clear Creek and Boulder Counties, Colorado, USGS Professional Paper 94, 379 pp.
Lovering, T.S., Goddard, E.N. (1950) Geology and ore deposits of the Front Range, Colorado. Professional Paper 223. US Geological Survey doi:10.3133/pp223
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