A manganese prospect on the west side of the North Fork of the Skokomish River north of the mouth of Copper Creek. Manganese silicates and jasper were exposed by a cut at the contact of greenstone and argillite.
Tectonics: Active Margin (Leading Edge Of North American Plate)

Deposit: Mn silicate body at greenstone-red calcareous argillite contact.

Development: Several open cuts, shallow shaft.

Rock formation(s): Metchosin Volcanics
Metchosin

Ore(s): Ore Along Greenstone-Red Calc Argillite Contact

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.

ⓘ Manganese

Mineral List

ⓘ Bementite

1 valid mineral.

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

ⓘ 'Argillite'

ⓘ Greenstone

Detailed Mineral List:

ⓘ Bementite

Formula: Mn₇Si₆O₁₅(OH)₈

References:

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

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 9 - Silicates
ⓘ	Bementite	9.EE.05	Mn₇Si₆O₁₅(OH)₈

List of minerals for each chemical element

H	Hydrogen
H	ⓘ Bementite	Mn₇Si₆O₁₅(OH)₈
O	Oxygen
O	ⓘ Bementite	Mn₇Si₆O₁₅(OH)₈
Si	Silicon
Si	ⓘ Bementite	Mn₇Si₆O₁₅(OH)₈
Mn	Manganese
Mn	ⓘ Bementite	Mn₇Si₆O₁₅(OH)₈

Other Databases

Link to USGS MRDS:	10095773

Other Regions, Features and Areas containing this locality

North AmericaContinent

Coast MountainsMountain Range

North America PlateTectonic Plate

Pacific Coast RangesAccretionary Complex
Siletzia DomainDomain
Western Washington–Oregon BasinsBasin

USA

Washington
- Olympic Mining DistrictMining District

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References

Green, S.T. (1945) Manganese Deposits of the Olympic Peninsula, Washington. State of Washington Department of Conservation and Development Division of Mines and Mining Report of Investigations No. 7, 49 pages.

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