Vote for your favorite mineral in #MinCup26! - Quartz vs. Asagiite
It's a classic vs a newbie as the most common named mineral in the crust Quartz is up against an exceedingly-rare sea foam-green mineral discovered just a few years ago Asagiite.
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Skunk Creek outcrops, Madison County, Montana, USAi
Regional Level Types
Skunk Creek outcropsGroup of Outcrops
Madison CountyCounty
MontanaState
USACountry

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PhotosMapsSearch
08428670017272332532926.jpg
Gedrite, etc.

Skunk Creek outcrops, Madison County, Montana, USA
08428670017272332532926.jpg
Gedrite, etc.

Skunk Creek outcrops, Madison County, Montana, USA
08428670017272332532926.jpg
Gedrite, etc.

Skunk Creek outcrops, Madison County, Montana, USA
Latitude & Longitude (WGS84):
45° 20' 33'' North , 111° 57' 11'' West
Latitude & Longitude (decimal):
45.34250,-111.95306
GeoHash:
G#: c803uqq70
GRN:
N31W57
Type:
Group of Outcrops
Köppen climate type:
Dfb : Warm-summer humid continental climate
Nearest Settlements:
PlacePopulationDistance
Virginia City199 (2017)5.4km
Alder103 (2011)12.2km
Ennis884 (2017)17.5km
Sheridan677 (2017)22.8km
Pony118 (2011)35.4km
Mindat Locality ID:
263477
Long-form identifier:
mindat:1:2:263477:0
GUID (UUID V4):
0


Outcrops along Skunk Creek near Granite Creek expose rocks of the Spuhler Peak metamorphic suite and include coarse orthoamphibole-garnet gneisses, amphibolite, sillimanite schist and quartzite.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


4 valid minerals.

Detailed Mineral List:

ⓘ Anthophyllite
Formula: ◻{Mg2}{Mg5}(Si8O22)(OH)2
ⓘ 'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ 'Garnet Group'
Formula: X3Z2(SiO4)3
ⓘ Gedrite
Formula: ◻{Mg2}{Mg3Al2}(Al2Si6O22)(OH)2
ⓘ 'Hornblende Root Name Group'
Formula: ◻Ca2(Z2+4Z3+)(AlSi7O22)(OH,F,Cl)2
ⓘ Quartz
Formula: SiO2
ⓘ Sillimanite
Formula: Al2(SiO4)O

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘQuartz4.DA.05SiO2
Group 9 - Silicates
ⓘSillimanite9.AF.05Al2(SiO4)O
ⓘAnthophyllite9.DD.05◻{Mg2}{Mg5}(Si8O22)(OH)2
ⓘGedrite9.DD.05◻{Mg2}{Mg3Al2}(Al2Si6O22)(OH)2
Unclassified
ⓘ'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ'Hornblende Root Name Group'-◻Ca2(Z2+4Z3+)(AlSi7O22)(OH,F,Cl)2
ⓘ'Garnet Group'-X3Z2(SiO4)3

List of minerals for each chemical element

HHydrogen
Hⓘ Anthophyllite◻{Mg2}{Mg5}(Si8O22)(OH)2
Hⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Hⓘ Gedrite◻{Mg2}{Mg3Al2}(Al2Si6O22)(OH)2
Hⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
OOxygen
Oⓘ Anthophyllite◻{Mg2}{Mg5}(Si8O22)(OH)2
Oⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Oⓘ Gedrite◻{Mg2}{Mg3Al2}(Al2Si6O22)(OH)2
Oⓘ QuartzSiO2
Oⓘ SillimaniteAl2(SiO4)O
Oⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
Oⓘ Garnet GroupX3Z2(SiO4)3
FFluorine
Fⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Fⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
MgMagnesium
Mgⓘ Anthophyllite◻{Mg2}{Mg5}(Si8O22)(OH)2
Mgⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Mgⓘ Gedrite◻{Mg2}{Mg3Al2}(Al2Si6O22)(OH)2
AlAluminium
Alⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Alⓘ Gedrite◻{Mg2}{Mg3Al2}(Al2Si6O22)(OH)2
Alⓘ SillimaniteAl2(SiO4)O
Alⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
SiSilicon
Siⓘ Anthophyllite◻{Mg2}{Mg5}(Si8O22)(OH)2
Siⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Siⓘ Gedrite◻{Mg2}{Mg3Al2}(Al2Si6O22)(OH)2
Siⓘ QuartzSiO2
Siⓘ SillimaniteAl2(SiO4)O
Siⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
Siⓘ Garnet GroupX3Z2(SiO4)3
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
CaCalcium
Caⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
TiTitanium
Tiⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
FeIron
Feⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2

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

Vitaliano, C. J. & W. Cordua compilers (1979): Geologic map of the southern Tobacco Root Mountains, Madison County, Montana: Geological Society of America: Map and Chart Series MC-31.
Burger, H.R. et. al. (2004) Geology and geochemistry of the Spuhler Peak metamorphic suite: in Precambrian Geology of the Tobacco Root Mountains, Montana: Geological Society of America Special Paper 377: 47-70
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