Horseshoe Basin Prospect, Nighthawk Mining District, Okanogan County, Washington, USA i
Regional Level Types
Horseshoe Basin Prospect Prospect
Nighthawk Mining District Mining District
Okanogan County County
Washington State
USA Country

A molybdenum prospect on the south side of Arnold Peak above Horseshoe Basin. The ore occurred as sparse sulfides in pegmatite dikes in schist. An open cut was the only development.
Structure: Host Rocks Are Remnant Of Roof Pendant; Dikes Of Qtz Monzonite Cut The Gneiss And Schist.

Commodity: Production in 1941

Rock formation(s): Similkameen Composite Pluton
Horseshoe Basin

Ore(s): In Pegmatite Vein

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.

ⓘ Molybdenum

Mineral List

ⓘ Ferrimolybdite

ⓘ Molybdenite

ⓘ Quartz

3 valid minerals.

Rock Types Recorded

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

Select Rock List Type

Alphabetical List Tree Diagram

ⓘ Gneiss

ⓘ Hornblendite

ⓘ Quartz-monzonite

Detailed Mineral List:

ⓘ Ferrimolybdite

Formula: Fe₂(MoO₄)₃ · nH₂O

References:

Phillips Purdy, C. (1954) Molybdenum Occurrences of Washington. Report of Investigations No.18, Division of Mines and Geology, Department of Conservations and Development, Washington, 125 pages.

ⓘ Molybdenite

Formula: MoS₂

References:

Phillips Purdy, C. (1954) Molybdenum Occurrences of Washington. Report of Investigations No.18, Division of Mines and Geology, Department of Conservations and Development, Washington, 125 pages.

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

ⓘ Quartz

Formula: SiO₂

References:

Phillips Purdy, C. (1954) Molybdenum Occurrences of Washington. Report of Investigations No.18, Division of Mines and Geology, Department of Conservations and Development, Washington, 125 pages.

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘ	Molybdenite	2.EA.30	MoS₂
Group 4 - Oxides and Hydroxides
ⓘ	Quartz	4.DA.05	SiO₂
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘ	Ferrimolybdite	7.GB.30	Fe₂(MoO₄)₃ · nH₂O

List of minerals for each chemical element

H	Hydrogen
H	ⓘ Ferrimolybdite	Fe₂(MoO₄)₃ · nH₂O
O	Oxygen
O	ⓘ Ferrimolybdite	Fe₂(MoO₄)₃ · nH₂O
O	ⓘ Quartz	SiO₂
Si	Silicon
Si	ⓘ Quartz	SiO₂
S	Sulfur
S	ⓘ Molybdenite	MoS₂
Fe	Iron
Fe	ⓘ Ferrimolybdite	Fe₂(MoO₄)₃ · nH₂O
Mo	Molybdenum
Mo	ⓘ Ferrimolybdite	Fe₂(MoO₄)₃ · nH₂O
Mo	ⓘ Molybdenite	MoS₂

Other Databases

Link to USGS MRDS:	10041654

Other Regions, Features and Areas containing this locality

North AmericaContinent

Cascade RangeMountain Range

North America PlateTectonic Plate

Okanagan TerraneOphiolite Complex
Western Quesnellia DomainDomain

USA

Washington
- Okanogan County
  - Pasayten WildernessWilderness Area
- Whatcom County
  - Pasayten WildernessWilderness Area

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

Phillips Purdy, C. (1954) Molybdenum Occurrences of Washington. Report of Investigations No.18, Division of Mines and Geology, Department of Conservations and Development, Washington, 125 pages.

Staatz, M.H., Weis, P.L., Tabor, R.W., Robertson, J.F., Van Noy, R.M., Pattee, E.C., Holt, D.C. (1971) Mineral Resources of the Pasayten Wilderness Area, Washington. US Geological Survey Bulletin 1325

Valentine, Grant M., Huntting, Marshall T. (1960) Part II - Metallic Minerals, in Inventory of Washington Minerals. Vol II. Bulletin 37, Washington Geological Survey.

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