Forge Ni-Cu

Occurrence in Sweet Grass county in Montana, United States with commodities Nickel, Copper, Cobalt, Platinum, Palladium, Rhodium, PGE, Silver, Gold
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Commodities
  6. Materials information
  7. Alteration
  8. Mineral occurrence model information
  9. Host and associated rocks
  10. Nearby scientific data
  11. Geologic structures
  12. Ore body information
  13. Controls for ore emplacement
  14. Economic information about the deposit and operations
  15. Mining district
  16. Land status
  17. Ownership information
  18. Links to other databases
  19. Bibliographic references
  20. General comments
  21. Reporter information

Geologic information

Identification information

Deposit ID 10048504
MRDS ID MP00094
Record type Site
Current site name Forge Ni-Cu
Alternate or previous names Placer Basin, Boulder Forge

Geographic coordinates

Geographic coordinates: -110.10497, 45.42325 (WGS84)
Elevation 2731
Location accuracy 1000(meters)
Relative position ABOUT 3.3 MI SOUTH OF CAMP LAKE, Est Imated Using Page And Nokleberg

Site location context

Political divisions (FIPS codes)

Sweet Grass(county)

Montana(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Picket Pin Mountain(quadrangle 1:24,000 scale)

Gardiner(quadrangle 1:100,000 scale)

Bozeman(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Upper Yellowstone(hydrologic unit)

Upper Yellowstone(hydrologic accounting unit)

Upper Yellowstone(hydrologic subregion)

Missouri(hydrologic region)

Federal lands

Custer Gallatin National Forest(National Forest)

National Forest FS(Type of land area)

FS(Federal land areas administered by FS)

Geographic areas

Country State County
United States Montana Sweet Grass

Comments on the location information

  • UNSURVEYED. IN GALLATIN NATIONAL FOREST. LOCATION GIVEN IS JUST NORTH OF FORGE CREEK ON WEST SIDE OF PLACER BASIN

Commodities

Commodity Importance
Nickel Critical Primary
Copper Primary
Cobalt Critical Secondary
Platinum Critical Secondary
Palladium Critical Secondary
Rhodium Critical Secondary
PGE Critical Tertiary
Silver Tertiary
Gold Tertiary

Comments on the commodity information

  • SEE PAGE (1979) FOR GENERAL DESCRIPTION OF BASAL SERIES MINERALIZATION.

Materials information

Materials Type of material
Chalcopyrite Ore
Pentlandite Ore
Pyrrhotite Ore
Magnetite Gangue
Plagioclase Gangue

Alteration

  • (Local) None Related To Ore-Forming Process

Analytical data

Result AVERAGE PGE IN SURFACE SAMPLES: 19.5 PPB PT, 73.0 PPB PD, <5 PPB RH (MAX.: 62 PPB PT, 210 PPB PD, 9 PPB RH)

Mineral occurrence model information

Model code 1
USGS model code 1
Deposit model name Stillwater Ni-Cu

Host and associated rocks

  • Host or associated Host
    Rock type Plutonic Rock > Ultramafic Intrusive Rock > Peridotite
    Stratigraphic age (youngest) Early Cretaceous
    Stratigraphic age (youngest) Neoarchean
  • Host or associated Host
    Rock type Metamorphic Rock > Hornfels

Nearby scientific data

(1) -110.10497, 45.42325

Economic information

Geologic structures

Type of structure Regional
Structure 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)

Ore body information

  • General form STRATIFORM, PODS, LENSES, DISSEMINATED
    Depth to top 0M

Controls for ore emplacement

  • Immiscible Sulfide Liquid Enriched In Ni And Cu Exsolved From Mafic Silicate Magma And Accumulated Near Lower Contact Of The Stillwater Complex. Assimilation Of Sulfur From Rocks Adjacent To The Stillwater Complex May Have Led To The Exsolution Of The Sulfide Liquid (Zientek And Ripley, 1990)

Comments on the geologic information

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

Economic information about the deposit and operations

Development status Occurrence
Commodity type Metallic
Deposit size Small
Significant No
Discovery year 1932

Mining district

District name In Stillwater Complex

Land status

Ownership category National Forest

Ownership information

  • Type Operator
    Owner Amax, Inc.
    First year 1968

Comments on the workings information

  • DIAMOND DRILLING 1967: 4 HOLES TOTALING 1,861 FT; 1969, 6 HOLES TOTALLING 2,700 FT

Reference information

Bibliographic references

General comments

Subject category Comment text
Deposit DEPOSIT IS PROBABLY SIMILAR TO MOUAT. LOW GRADE
Deposit Discovery Year: BEFORE EARLY 1930'S

Reporter information

Type Date Name Affiliation Comment
Reporter 01-OCT-91 Peterson, Jocelyn A. U.S. Geological Survey

Beyond USGS

Supplemental information added by qvyshift.com. Not part of the original USGS MRDS record.

Operator history (post-MRDS)

MRDS records operators as of each record's last update (≤ 2019). Some of the operators listed here have since changed hands or dissolved:

Curated by qvyshift.com from publicly-reported M&A activity (SEC filings, press releases, USGS Mineral Yearbooks). Not authoritative — verify against primary sources before relying on it. The MSHA panel above is the current authoritative source for actively-permitted mines.