Vote for your favorite mineral in #MinCup26! - Sphalerite vs. Anorthite
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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Horseshoe Mine, Middle Fork of the Snoqualmie River, Snoqualmie Mining District, King County, Washington, USAi
Regional Level Types
Horseshoe MineProspect
Middle Fork of the Snoqualmie RiverRiver
Snoqualmie Mining DistrictMining District
King CountyCounty (Historical)
WashingtonState
USACountry

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PhotosMapsSearch
Latitude & Longitude (WGS84):
47° 28' 14'' North , 121° 37' 40'' West
Latitude & Longitude (decimal):
47.47067,-121.62786
GRN:
N32W60
Type:
Prospect
Köppen climate type:
Csb : Warm-summer Mediterranean climate
Nearest Settlements:
PlacePopulationDistance
Tanner1,018 (2011)8.9km
Riverbend2,132 (2011)9.2km
Wilderness Rim1,523 (2017)10.9km
North Bend6,679 (2017)12.3km
Snoqualmie13,169 (2017)16.2km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Bellevue Rock Club, Inc.Bellevue, Washington46km
Cascade Mineralogical Society IncKent, Washington47km
North American Miners AssociationKent, Washington47km
East KingCo Rock ClubKirkland, Washington49km
Mindat Locality ID:
15853
Long-form identifier:
mindat:1:2:15853:1
GUID (UUID V4):
0


Old copper workings above Granite Creek, developed by several short adits. Small quartz crystals were found in vugs, and some quartz crystals display fluorescent phantoms under short-wave UV.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


3 valid minerals.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘChalcopyrite2.CB.10aCuFeS2
ⓘPyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
ⓘQuartz4.DA.05SiO2

List of minerals for each chemical element

OOxygen
Oⓘ QuartzSiO2
SiSilicon
Siⓘ QuartzSiO2
SSulfur
Sⓘ ChalcopyriteCuFeS2
Sⓘ PyriteFeS2
FeIron
Feⓘ ChalcopyriteCuFeS2
Feⓘ PyriteFeS2
CuCopper
Cuⓘ ChalcopyriteCuFeS2

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

Cannon, Bart (1975) Minerals of Washington. Cordilleran. 184 pp.
Jacobson, D., Pisoni, V., Cady, G., Woodhouse, P. (2008) Discovering Washington's Historic Mines, Volume 1: The West Central Cascade Mountains. Northwest Mining Publishers, 230 pages.
He, Eric (2019) Minerals of King County, Washington. https://www.mindat.org/a/kingco_minerals
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