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Bear Basin Mines, Buena Vista Mining District, King County, Washington, USAi
Regional Level Types
Bear Basin MinesGroup of Mines
Buena Vista Mining DistrictMining District
King CountyCounty (Historical)
WashingtonState
USACountry

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Latitude & Longitude (WGS84):
47° 38' 22'' North , 121° 29' 10'' West
Latitude & Longitude (decimal):
Type:
Group of Mines
Nearest Settlements:
PlacePopulationDistance
Skykomish207 (2017)12.2km
Baring220 (2011)14.9km
Index194 (2017)20.8km
Tanner1,018 (2011)26.7km
May Creek818 (2011)27.4km
Mindat Locality ID:
15288
Long-form identifier:
mindat:1:2:15288:3
GUID (UUID V4):
0
Other/historical names associated with this locality:
Bear Basin property; Bear Creek prospects; Snoqualmie Mines; Cascade Mines


25 MI BY ROAD FROM NORTH BEND; ABOUT 0.5 MI NORTHWEST OF LENNOX LAKE.

A Ag-Pb-Cu-Au-Sb-Sn-As occurrence/group of mines located in the SW¼ sec. 13, SE¼ sec. 14, NE¼ sec. 23 & in the NW¼ sec. 24, T25N, R10E, WM, 25 miles by road from North End (town), about 0.5 mile NW of Lennox Lake, in/around the glacial cirque at the head of Bear Creek, on National Forest wilderness land (Alpine Lakes Wilderness In Mount Baker-Snoqualmie National Forest). Owned by the Bear Basin Mining Company, Bremerton, Washington (1952-). The claims were registered in 1905 and the last major work occurred in 1934. The USGS MRDS database stated accuracy for this locality is 10 meters.

Mineralization is a polymetallic deposit (Mineral occurrence model information: Model code: 85; USGS model code: 22c; Deposit model name: Polymetallic veins; Mark3 model number: 46), hosted in Miocene diorite of the Northern Phaase of the Snoqualmie BAtholith. The ore body is a vein deposit that strikes N75W & N50W, dips 75-80SW & steep, at a thickness of 1.22 meters, and a length of 1,066.8 meters. Two sets of mineralized shear zones contain quartz stringers at 5.9 feet wide in adit No. 3. Other adits were also driven on shear zones. Local alteration includes sericitization, kaolinization and silicification. Local rocks include Tertiary granitic rocks.

Local geologic structures include steeply-dipping shear zones.

Workings include underground openings. There are 8 adits and a winze in the basin that had a total of 2,165 feet of workings which were driven by the Snoqualmie Mining Company. The company built a small mill on the creek around 1917. A 1,500 foot long aerial tram was built to the No. 3 adit then moved to the No. 6. Before this tram could be used, the mill burned down in 1934 and little has been done since. As of 2015, adits No. 2 and No. 8 are collapsed.

Production was a small quantity of Ag produced by 1922.

The mines assayed high in silver and showed some gold. Analytical data results: Sample in adit assayed 0.06 ounce/ton Au, 16.9 ounce/ton Ag, 0.13% Zn. Samples from adit No. 3 showed 0.1-33.7 ounces/ton Ag, a maximum of 0.05 ounce/ton Au, and a maximum of 0.16% Cu.

Reserves are estimated to be small but several areas may be favorable for exploration.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.


Mineral List


21 valid minerals. 1 (TL) - type locality of valid minerals.

Rock Types Recorded


Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

Albite
Formula: Na(AlSi3O8)
Habit: shrp crystlas to 1/2"
Colour: white
'Andorite'
Formula: AgPbSb3S6
Habit: grains and poorly formed crystals
Arsenopyrite
Formula: FeAsS
Chalcopyrite
Formula: CuFeS2
'Chlorite Group'
Coronadite
Formula: Pb(Mn4+6Mn3+2)O16
References:
Dr. Günter Grundmann collectionIdentified by Dr. Günter Grundmann: Polarised-light microscopy
'Freibergite Subgroup'
Formula: (Ag6,[Ag6]4+)(Cu4 C2+2)Sb4S12S0-1
Galena
Formula: PbS
Jamesonite
Formula: Pb4FeSb6S14
Kaolinite
Formula: Al2(Si2O5)(OH)4
Lasmanisite (TL)
Formula: Ag12Pb13Mn11Sb44S96
Type Locality:
Molybdenite
Formula: MoS2
Muscovite
Formula: KAl2(AlSi3O10)(OH)2
Muscovite var. Sericite
Formula: KAl2(AlSi3O10)(OH)2
Pyrite
Formula: FeS2
Quartz
Formula: SiO2
Quatrandorite
Formula: AgPbSb3S6
References:
Dr. Günter Grundmann collectionIdentified by Dr. Günter Grundmann: Polarised-light microscopy
Ramdohrite ?
Formula: Pb5.9Fe0.1Mn0.1In0.1Cd0.2Ag2.8Sb10.8S24
Description: Analytical details needed.
Rhodochrosite
Formula: MnCO3
Senandorite
Formula: AgPbSb3S6
References:
Dr. Günter Grundmann collectionIdentified by Dr. Günter Grundmann: Polarised-light microscopy
Sphalerite
Formula: ZnS
Stannite
Formula: Cu2FeSnS4
Stibnite
Formula: Sb2S3
'Tetrahedrite Subgroup'
Formula: Cu6(Cu4C2+2)Sb4S12S
Todorokite
Formula: (Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O
References:
Dr. Günter Grundmann collectionIdentified by Dr. Günter Grundmann: Polarised-light microscopy
'Tourmaline'
Formula: AD3G6(T6O18)(BO3)3X3Z
Uchucchacuaite
Formula: AgMnPb3Sb5S12

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
Sphalerite2.CB.05aZnS
Chalcopyrite2.CB.10aCuFeS2
Stannite2.CB.15aCu2FeSnS4
Galena2.CD.10PbS
Stibnite2.DB.05Sb2S3
Molybdenite2.EA.30MoS2
Pyrite2.EB.05aFeS2
Arsenopyrite2.EB.20FeAsS
'Freibergite Subgroup'2.GB.05(Ag6,[Ag6]4+)(Cu4 C2+2)Sb4S12S0-1
'Tetrahedrite Subgroup'2.GB.05Cu6(Cu4C2+2)Sb4S12S
Jamesonite2.HB.15Pb4FeSb6S14
Senandorite2.JB.AgPbSb3S6
Lasmanisite (TL)2.JB.Ag12Pb13Mn11Sb44S96
Ramdohrite ?2.JB.40aPb5.9Fe0.1Mn0.1In0.1Cd0.2Ag2.8Sb10.8S24
Uchucchacuaite2.JB.40aAgMnPb3Sb5S12
Quatrandorite2.JB.40aAgPbSb3S6
Group 4 - Oxides and Hydroxides
Quartz4.DA.05SiO2
Coronadite4.DK.05aPb(Mn4+6Mn3+2)O16
Todorokite4.DK.10(Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O
Group 5 - Nitrates and Carbonates
Rhodochrosite5.AB.05MnCO3
Group 9 - Silicates
Muscovite9.EC.15KAl2(AlSi3O10)(OH)2
var. Sericite9.EC.15KAl2(AlSi3O10)(OH)2
Kaolinite9.ED.05Al2(Si2O5)(OH)4
Albite9.FA.35Na(AlSi3O8)
Unclassified
'Andorite'-AgPbSb3S6
'Chlorite Group'-
'Tourmaline'-AD3G6(T6O18)(BO3)3X3Z

List of minerals for each chemical element

HHydrogen
H KaoliniteAl2(Si2O5)(OH)4
H MuscoviteKAl2(AlSi3O10)(OH)2
H Todorokite(Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O
H Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
BBoron
B TourmalineAD3G6(T6O18)(BO3)3X3Z
CCarbon
C RhodochrositeMnCO3
OOxygen
O AlbiteNa(AlSi3O8)
O CoronaditePb(Mn64+Mn23+)O16
O KaoliniteAl2(Si2O5)(OH)4
O MuscoviteKAl2(AlSi3O10)(OH)2
O QuartzSiO2
O RhodochrositeMnCO3
O Todorokite(Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O
O TourmalineAD3G6(T6O18)(BO3)3X3Z
O Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
NaSodium
Na AlbiteNa(AlSi3O8)
Na Todorokite(Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O
MgMagnesium
Mg Todorokite(Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O
AlAluminium
Al AlbiteNa(AlSi3O8)
Al KaoliniteAl2(Si2O5)(OH)4
Al MuscoviteKAl2(AlSi3O10)(OH)2
Al Todorokite(Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O
Al Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SiSilicon
Si AlbiteNa(AlSi3O8)
Si KaoliniteAl2(Si2O5)(OH)4
Si MuscoviteKAl2(AlSi3O10)(OH)2
Si QuartzSiO2
Si Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
SSulfur
S AndoriteAgPbSb3S6
S ArsenopyriteFeAsS
S ChalcopyriteCuFeS2
S Freibergite Subgroup(Ag6,[Ag6]4+)(Cu4 C22+)Sb4S12S0-1
S GalenaPbS
S JamesonitePb4FeSb6S14
S MolybdeniteMoS2
S PyriteFeS2
S RamdohritePb5.9Fe0.1Mn0.1In0.1Cd0.2Ag2.8Sb10.8S24
S SphaleriteZnS
S StanniteCu2FeSnS4
S StibniteSb2S3
S Tetrahedrite SubgroupCu6(Cu4C22+)Sb4S12S
S UchucchacuaiteAgMnPb3Sb5S12
S QuatrandoriteAgPbSb3S6
S SenandoriteAgPbSb3S6
S LasmanisiteAg12Pb13Mn11Sb44S96
KPotassium
K MuscoviteKAl2(AlSi3O10)(OH)2
K Todorokite(Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O
K Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CaCalcium
Ca Todorokite(Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O
MnManganese
Mn CoronaditePb(Mn64+Mn23+)O16
Mn RamdohritePb5.9Fe0.1Mn0.1In0.1Cd0.2Ag2.8Sb10.8S24
Mn RhodochrositeMnCO3
Mn Todorokite(Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O
Mn UchucchacuaiteAgMnPb3Sb5S12
Mn LasmanisiteAg12Pb13Mn11Sb44S96
FeIron
Fe ArsenopyriteFeAsS
Fe ChalcopyriteCuFeS2
Fe JamesonitePb4FeSb6S14
Fe PyriteFeS2
Fe RamdohritePb5.9Fe0.1Mn0.1In0.1Cd0.2Ag2.8Sb10.8S24
Fe StanniteCu2FeSnS4
CuCopper
Cu ChalcopyriteCuFeS2
Cu Freibergite Subgroup(Ag6,[Ag6]4+)(Cu4 C22+)Sb4S12S0-1
Cu StanniteCu2FeSnS4
Cu Tetrahedrite SubgroupCu6(Cu4C22+)Sb4S12S
ZnZinc
Zn SphaleriteZnS
AsArsenic
As ArsenopyriteFeAsS
SrStrontium
Sr Todorokite(Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O
MoMolybdenum
Mo MolybdeniteMoS2
AgSilver
Ag AndoriteAgPbSb3S6
Ag Freibergite Subgroup(Ag6,[Ag6]4+)(Cu4 C22+)Sb4S12S0-1
Ag RamdohritePb5.9Fe0.1Mn0.1In0.1Cd0.2Ag2.8Sb10.8S24
Ag UchucchacuaiteAgMnPb3Sb5S12
Ag QuatrandoriteAgPbSb3S6
Ag SenandoriteAgPbSb3S6
Ag LasmanisiteAg12Pb13Mn11Sb44S96
CdCadmium
Cd RamdohritePb5.9Fe0.1Mn0.1In0.1Cd0.2Ag2.8Sb10.8S24
InIndium
In RamdohritePb5.9Fe0.1Mn0.1In0.1Cd0.2Ag2.8Sb10.8S24
SnTin
Sn StanniteCu2FeSnS4
SbAntimony
Sb AndoriteAgPbSb3S6
Sb Freibergite Subgroup(Ag6,[Ag6]4+)(Cu4 C22+)Sb4S12S0-1
Sb JamesonitePb4FeSb6S14
Sb RamdohritePb5.9Fe0.1Mn0.1In0.1Cd0.2Ag2.8Sb10.8S24
Sb StibniteSb2S3
Sb Tetrahedrite SubgroupCu6(Cu4C22+)Sb4S12S
Sb UchucchacuaiteAgMnPb3Sb5S12
Sb QuatrandoriteAgPbSb3S6
Sb SenandoriteAgPbSb3S6
Sb LasmanisiteAg12Pb13Mn11Sb44S96
BaBarium
Ba Todorokite(Na,Ca,K,Ba,Sr)1-x(Mn,Mg,Al)6O12 · 3-4H2O
PbLead
Pb AndoriteAgPbSb3S6
Pb CoronaditePb(Mn64+Mn23+)O16
Pb GalenaPbS
Pb JamesonitePb4FeSb6S14
Pb RamdohritePb5.9Fe0.1Mn0.1In0.1Cd0.2Ag2.8Sb10.8S24
Pb UchucchacuaiteAgMnPb3Sb5S12
Pb QuatrandoriteAgPbSb3S6
Pb SenandoriteAgPbSb3S6
Pb LasmanisiteAg12Pb13Mn11Sb44S96

Other Databases

Link to USGS MRDS:10094251

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate

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