Chrome Mountain Ni-Cu

The Chrome Mountain Ni-Cu is a copper and nickel mine located in Sweet Grass county, Montana at an elevation of 9,541 feet.

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

MRDS mine locations are often very general, and in some cases are incorrect. Some mine remains have been covered or removed by modern industrial activity or by development of things like housing. The satellite view offers a quick glimpse as to whether the MRDS location corresponds to visible mine remains.

Site Name

Primary: Chrome Mountain Ni-Cu

Commodity

Primary: Copper
Primary: Nickel
Secondary: Cobalt
Secondary: Platinum
Secondary: Palladium
Secondary: Rhodium
Tertiary: PGE
Tertiary: Silver
Tertiary: Gold

Location

State: Montana
County: Sweet Grass
District: In Stillwater Complex

Land Status

Land ownership: National Forest
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

Owner Name: Johns-Manville Products Corp.
Years: 1979 -

Production

Not available

Deposit

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

Physiography

General Physiographic Area: Rocky Mountain System
Physiographic Province: Middle Rocky Mountains

Mineral Deposit Model

Model Name: Stillwater Ni-Cu

Orebody

Form: STRATIFORM, PODS, LENSES

Structure

Type: R
Description: The Stillwater Complex Is Exposed Along The Northern Margin Of The Beartooth Uplift, One Of Several Laramide Basement-Cored Ranges That Make Up The Rocky Mountain Foreland Of South-Central Montana (Foose And Others, 1961: Kulik And Schmidt, 1988)

Alterations

Alteration Type: L
Alteration Text: None Related To Ore-Forming Process

Rocks

Name: Peridotite
Role: Host
Age Type: Host Rock
Age Young: Early Cretaceous

Name: Peridotite
Role: Host
Age Type: Associated Rock Unit
Age Young: Neoarchean

Analytical Data

Analytical Data: AVERAGE PGE IN SURFACE SAMPLES: 16.9 PPB PT, 37.6 PPB PD, <5 PPB RH (MAX.: 67 PPB PT, 130 PPB PD, 9 PPB RH)

Materials

Ore: Pyrrhotite
Ore: Pentlandite
Ore: Chalcopyrite
Gangue: Magnetite
Gangue: Plagioclase

Comments

Comment (Deposit): DEPOSIT IS PROBABLY SIMILAR TO MOUAT

Comment (Commodity): SEE PAGE (1979) FOR GENERAL DESCRIPTION OF BASAL SERIES MINERALIZATION.

Comment (Location): UNSURVEYED. IN CUSTER NATIONAL FOREST. GENERALIZED LOCATION

Comment (Geology): AGE OF STILLWATER COMPLEX IS 2,705 +/- 4 MA BASED ON U-PB SYSTEMATICS ON ZIRCON-BADDELEYITE (PREMO AND OTHERS, 1990)

References

Reference (Deposit): PAGE, N.J, AND NOKLEBERG, W.J., 1974, GEOLOGIC MAP OF THE STILLWATER COMPLEX, MONTANA: U.S. GEOLOGICAL SURVEY MISCELLANEOUS GEOLOGIC INVESTIGATIONS MAP I-797, SCALE 1:12,000.

Reference (Deposit): ZIENTEK, M.L., 1993, MINERAL RESOURCE APPRAISAL FOR LOCATABLE MINERALS: THE STILLWATER COMPLEX, IN HAMMARSTROM, J.M., ZIENTEK, M.L., AND ELLIOTT, J.E., EDS., MINERAL RESOURCE ASSESSMENT OF THE ABSAROKA-BEARTOOTH STUDY AREA, CUSTER AND GALLATIN NATIONAL FORESTS, MONTANA: U.S. GEOLOGICAL SURVEY OPEN-FILE REPORT 93-207, P. F1-F83.

Reference (Deposit): PAGE, N.J, ROWE, J.J., AND HAFFTY, JOSEPH, 1976, PLATINUM METALS IN THE STILLWATER COMPLEX, MONTANA: ECONOMIC GEOLOGY, V. 71, P. 1352-1363.

Reference (Deposit): PREMO, W.R., HELZ, R.T., ZIENTEK, M.L., AND LANGSTON, R.B., 1990, U-PB AND SM-ND AGES FOR THE STILLWATER COMPLEX AND ITS ASSOCIATED SILLS AND DIKES, BEARTOOTH MOUNTAINS, MONTANA: IDENTIFICATION OF A PARENT MAGMA?: GEOLOGY, V. 18, P. 1065-1068.

Reference (Deposit): ZIENTEK, M.L., AND RIPLEY, E.M., 1990, SULFUR ISOTOPIC STUDIES OF THE STILLWATER COMPLEX AND ASSOCIATED ROCKS, MONTANA: ECONOMIC GEOLOGY, V. 85, P. 376-391.

Reference (Deposit): PAGE, N.J, 1979, STILLWATER COMPLEX, MONTANA - STRUCTURE, MINERALOGY, AND PETROLOGY OF THE BASAL ZONE WITH EMPHASIS ON THE OCCURRENCE OF SULFIDES: U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 1038, 69 P.

Principal Gold Districts of Montana

In Montana, 54 mining districts have each have produced more than 10,000 ounces of gold. The largest producers are Butte, Helena, Marysville, and Virginia City, each having produced more than one million ounces. Twenty seven other districts are each credited with between 100,000 and one million ounces of gold production. Read more: Principal Gold Districts of Montana.