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Delmoe Lake area, Boulder Batholith, Jefferson County, Montana, USAi
Regional Level Types
Delmoe Lake areaArea
Boulder BatholithBatholith
Jefferson CountyCounty
MontanaState
USACountry

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Latitude & Longitude (WGS84):
46° North , 112° West (est.)
Estimate based on other nearby localities or region boundaries.
Margin of Error:
~53km
Type:
Mindat Locality ID:
211171
Long-form identifier:
mindat:1:2:211171:4
GUID (UUID V4):
0


Delmoe Lake, a reservoir located approximately 10 miles north of Homestake Pass in Jefferson County, Montana, is part of the larger mass of the Boulder Batholith and contains numerous bodies and segregations of aplite, grano-aplite, and alaskaites. These occasionally grade locally into coarse pegmatite or graphic granite, and then into vugs or cavities. The vugs contain anhedral to euhedral crystals of the characteristic granite minerals, i.e., quartz, feldspar, and mica minerals.

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

13 valid minerals.

Rock Types Recorded

Note: data is currently VERY limited. Please bear with us while we work towards adding this information!

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

Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ Albite
Formula: Na(AlSi3O8)
ⓘ Albite var. Cleavelandite
Formula: Na(AlSi3O8)
ⓘ 'Axinite Group'
References:
ⓘ Cosalite
Formula: Pb2Bi2S5
ⓘ Epidote
Formula: (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
References:
ⓘ 'Feldspar Group'
ⓘ 'Garnet Group'
Formula: X3Z2(SiO4)3
ⓘ Hematite
Formula: Fe2O3
ⓘ 'K Feldspar'
ⓘ Microcline
Formula: K(AlSi3O8)
References:
ⓘ Molybdenite
Formula: MoS2
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Muscovite var. Sericite
Formula: KAl2(AlSi3O10)(OH)2
References:
ⓘ Pyrite
Formula: FeS2
ⓘ Quartz
Formula: SiO2
Habit: Hexagonal
Colour: Black
Description: Morion (Smokey) Quartz, deep black hexagonal crystals
ⓘ Quartz var. Amethyst
Formula: SiO2
ⓘ Quartz var. Sceptre Quartz
Formula: SiO2
References:
ⓘ Quartz var. Smoky Quartz
Formula: SiO2
ⓘ Rutile
Formula: TiO2
ⓘ Schorl
Formula: NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH)
ⓘ Spessartine
Formula: Mn2+3Al2(SiO4)3
References:
ⓘ Topaz
Formula: Al2(SiO4)(F,OH)2
Habit: Orthorhombic
Colour: Gold, Yellow, Clear
Description: Light Golden colored, Well formed Topaz Crystal
ⓘ 'Tourmaline'
Formula: AD3G6(T6O18)(BO3)3X3Z

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘMolybdenite2.EA.30MoS2
ⓘPyrite2.EB.05aFeS2
ⓘCosalite2.JB.10Pb2Bi2S5
Group 4 - Oxides and Hydroxides
ⓘHematite4.CB.05Fe2O3
ⓘQuartz
var. Amethyst
4.DA.05SiO2
ⓘ4.DA.05SiO2
ⓘvar. Smoky Quartz4.DA.05SiO2
ⓘvar. Sceptre Quartz4.DA.05SiO2
ⓘRutile4.DB.05TiO2
Group 9 - Silicates
ⓘSpessartine9.AD.25Mn2+3Al2(SiO4)3
ⓘTopaz9.AF.35Al2(SiO4)(F,OH)2
ⓘEpidote9.BG.05a(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
ⓘSchorl9.CK.05NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH)
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘvar. Sericite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘMicrocline9.FA.30K(AlSi3O8)
ⓘAlbite9.FA.35Na(AlSi3O8)
ⓘvar. Cleavelandite9.FA.35Na(AlSi3O8)
Unclassified
ⓘ'Feldspar Group'-
ⓘ'Tourmaline'-AD3G6(T6O18)(BO3)3X3Z
ⓘ'K Feldspar'-
ⓘ'Garnet Group'-X3Z2(SiO4)3
ⓘ'Axinite Group'-

List of minerals for each chemical element

HHydrogen
Hⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
Hⓘ TopazAl2(SiO4)(F,OH)2
Hⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
BBoron
Bⓘ SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
Bⓘ TourmalineAD3G6(T6O18)(BO3)3X3Z
OOxygen
Oⓘ AlbiteNa(AlSi3O8)
Oⓘ Quartz var. AmethystSiO2
Oⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Oⓘ HematiteFe2O3
Oⓘ MicroclineK(AlSi3O8)
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ QuartzSiO2
Oⓘ RutileTiO2
Oⓘ SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
Oⓘ Quartz var. Smoky QuartzSiO2
Oⓘ SpessartineMn32+Al2(SiO4)3
Oⓘ TopazAl2(SiO4)(F,OH)2
Oⓘ TourmalineAD3G6(T6O18)(BO3)3X3Z
Oⓘ Quartz var. Sceptre QuartzSiO2
Oⓘ Albite var. CleavelanditeNa(AlSi3O8)
Oⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Oⓘ Garnet GroupX3Z2(SiO4)3
FFluorine
Fⓘ TopazAl2(SiO4)(F,OH)2
NaSodium
Naⓘ AlbiteNa(AlSi3O8)
Naⓘ SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
Naⓘ Albite var. CleavelanditeNa(AlSi3O8)
AlAluminium
Alⓘ AlbiteNa(AlSi3O8)
Alⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Alⓘ MicroclineK(AlSi3O8)
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
Alⓘ SpessartineMn32+Al2(SiO4)3
Alⓘ TopazAl2(SiO4)(F,OH)2
Alⓘ Albite var. CleavelanditeNa(AlSi3O8)
Alⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SiSilicon
Siⓘ AlbiteNa(AlSi3O8)
Siⓘ Quartz var. AmethystSiO2
Siⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Siⓘ MicroclineK(AlSi3O8)
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ QuartzSiO2
Siⓘ SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
Siⓘ Quartz var. Smoky QuartzSiO2
Siⓘ SpessartineMn32+Al2(SiO4)3
Siⓘ TopazAl2(SiO4)(F,OH)2
Siⓘ Quartz var. Sceptre QuartzSiO2
Siⓘ Albite var. CleavelanditeNa(AlSi3O8)
Siⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Siⓘ Garnet GroupX3Z2(SiO4)3
SSulfur
Sⓘ CosalitePb2Bi2S5
Sⓘ MolybdeniteMoS2
Sⓘ PyriteFeS2
KPotassium
Kⓘ MicroclineK(AlSi3O8)
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Kⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CaCalcium
Caⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
TiTitanium
Tiⓘ RutileTiO2
MnManganese
Mnⓘ SpessartineMn32+Al2(SiO4)3
FeIron
Feⓘ Epidote(CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)
Feⓘ HematiteFe2O3
Feⓘ PyriteFeS2
Feⓘ SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
MoMolybdenum
Moⓘ MolybdeniteMoS2
PbLead
Pbⓘ CosalitePb2Bi2S5
BiBismuth
Biⓘ CosalitePb2Bi2S5

Localities in this Region

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