Big Ledge Nickel-Copper Prospect

The Big Ledge Nickel-Copper Prospect is a nickel and copper mine located in Alaska.

About the MRDS Data:

All mine locations were obtained from the USGS Mineral Resources Data System. The locations and other information in this database have not been verified for accuracy. It should be assumed that all mines are on private property.

Mine Info

Satelite View

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Site Name

Primary: Big Ledge Nickel-Copper Prospect

Commodity

Primary: Nickel
Primary: Copper
Tertiary: Zinc

Location

State: Alaska
District: Chichagof

Land Status

Land ownership: State
Note: the land ownership field only identifies whether the area the mine is in is generally on public lands like Forest Service or BLM land, or if it is in an area that is generally private property. It does not definitively identify property status, nor does it indicate claim status or whether an area is open to prospecting. Always respect private property.

Holdings

Not available

Workings

Not available

Ownership

Not available

Production

Not available

Deposit

Record Type: Site
Operation Category: Occurrence
Operation Type: Unknown
Discovery Year: 1923
Years of Production:
Organization:
Significant: N
Deposit Size: S

Physiography

Not available

Mineral Deposit Model

Not available

Orebody

Not available

Structure

Not available

Alterations

Not available

Rocks

Name: Conglomerate
Role: Associated
Age Type: Associated Rock
Age Young: Late Devonian

Analytical Data

Not available

Materials

Ore: Chalcopyrite
Ore: Sphalerite
Ore: Pentlandite
Ore: Pyrrhotite
Gangue: Pyrite
Gangue: Quartz
Gangue: Calcite

Comments

Comment (Location): USGS MF-467, LOC. 48. LONGITUDE GIVEN IN USGS OF 78-450 IS INCORRECT. LAND STATUS VALUE CALCULATED 6-94 USING GIS OVERLAY ANALYSIS WITH BLM 1:2,500,000 SCALE OWNERSHIP STATUS MAP (1991).

Comment (Development): 2 CLAIMS STAKED IN 1923 BY ALFRED LAGERGREN. NO DEVELOPMENT WORK DONE.

Comment (Deposit): DEPOSIT IS IN GABBROIC OR DIABASE DIKE 20 FT. WIDE INTRUSIVE INTO CONGLOMERATE. 6 FT. OF CENTRAL PORTION OF DIKE SHEARED AND HIGHLY FRACTURED AND OXIDIZED, CONTAINS QUARTZ AND CALCITE STRINGERS WITH SULFIDE MINERALS, AND STRINGERS OF SOLID PYRRHOTITE UP TO 6 IN WIDE. DIKE CONTAINS DISSEMINATED PYRRHOTITE, CHALCOPYRITE, PENTLANDITE, SECONDARY NICKEL MINERALS, PYRITE, AND TRACE OF SPHALERITE. CHALCOPYRITE, PYRRHOTITE, AND PENTANDITE OCCUR IN VEIN-LIKE FORMS, AND ARE ASSOCIATED WITH EACH OTHER IN SMALL, VEIN-LIKE BLEBS.

Comment (Workings): NATURE OF WORKINGS NOT DEFINED

Comment (Geology): FRACTURES IN DIKE SHOW SLICKEN SLIDING, SIGNIFYING FAULT MOVEMENT SINCE EMPLACEMENT.

References

Reference (Deposit): USGS B 773, P. 107-108 (1925)

Reference (Deposit): USGS MF-467, LOC. 48 (1972)

Reference (Deposit): USGS OF 78-450, P. 17 (1978)

Reference (Other Database): BAG-MF-467-48

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