1. Mineral Resources
  2. Online Spatial Data
  3. Mineral Resource Data System (MRDS)

Little Rocky Creek Ni-Cu

Occurrence in Stillwater county in Montana, United States with commodities Nickel, Copper, Cobalt, PGE, Silver, Gold
Map
XML
JSON
KML
B

Geologic information

Identification information

Deposit ID 10042344
MRDS ID M060097
Record type Site
Current site name Little Rocky Creek Ni-Cu
Alternate or previous names Benbow, Rocky Group, Chrome Lake

Geographic coordinates

Geographic coordinates: -109.80551, 45.35714 (WGS84)
Elevation 2576
Location accuracy 100(meters)
Relative position ABOUT 0.5 MI NORTHWEST OF CHROME LAKE, Acc Generalized Location Of Adit Near Little Rocks Creek
(click for info)

Geographic areas

Country State County
United States Montana Stillwater

Public Land Survey System information

Meridian Township Range Section Fraction State
Montana Principal 005S 016E 31 Montana

Comments on the location information

  • UNSURVEYED. IN CUSTER NATIONAL FOREST

Commodities

Commodity Importance
Nickel Primary
Copper Primary
Cobalt Secondary
PGE 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 OF ANALYSES OF SURFACE SAMPLES: 32.8 PPB PT, 9.1 PPB PD (MAX. 190 PPB PT, 18 PPB PD)

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

Nearby scientific data

(1) -109.80551, 45.35714
ListMap

Geologic structures

Type Description Terms
Regional 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)
Local Local Faults Of Small Displacement

Ore body information

  • General form MASSIVE AND 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

Economic information about the deposit and operations

Development status Occurrence
Commodity type Metallic
Deposit size Small
Significant No
Discovery year 1883
Discoverer Jack Nye, Jimmy And Jonas Hedges

Mining district

District name In Stillwater Complex

Land status

Ownership category National Forest

Ownership information

  • Type Operator
    Owner Amoco Minerals Co. (Operated Rocky Group)
    First year 1985

Workings at the site

  • Type of workings Underground
    Length 91.44M

Comments on the workings information

  • 4 ADITS, INACCESSIBLE; 9 DIAMOND DRILL HOLES TOTALING 5,564 FT DRILLED IN 1967-1970; 14 DRILLHOLES IN 1983 TOTALLING 20,073 FT

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS M060097

Bibliographic references

  • Deposit

    ROBY, R.N., 1949, INVESTIGATION OF COPPER-NICKEL DEPOSITS OF THE STILLWATER COMPLEX, STILLWATER AND SWEETGRASS COUNTIES, MONTANA: U.S. BUREAU OF MINES REPORT OF INVESTIGATIONS 4431, P. 10.

  • Deposit

    HOWLAND, A.L., PEOPLES, J.W., AND SAMPSON, EDWARD, 1936, THE STILLWATER IGNEOUS COMPLEX AND ASSOCIATED OCCURRENCES OF NICKEL AND PLATINUM GROUP METALS: MONTANA BUREAU OF MINES AND GEOLOGY MISCELLANEOUS CONTRIBUTION 7, P. 11.

  • Deposit

    PAGE, N.J, RILEY, L.B., AND HAFFTY, JOSEPH, 1969, PLATINUM, PALLADIUM, AND RHODIUM ANALYSES OF ULTRAMAFIC AND MAFIC ROCKS FROM THE STILLWATER COMPLEX, MONTANA: U.S. GEOLOGICAL SURVEY CIRCULAR 624, P. 6.

  • Deposit

    PAGE, N.J, RILEY, L.B., AND HAFFTY, JOSEPH, 1972, VERTICAL AND LATERAL VARIATION OF PLATINUM, PALLADIUM, AND RHODIUM IN THE STILLWATER COMPLEX, MONTANA: ECONOMIC GEOLOGY, V. 67, P. 1356-1357.

  • 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.

  • 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.

  • 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.

  • 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.

Reporter information

Type Date Name Affiliation Comment
Reporter 01-JAN-73 Dohrenwend, John C. U.S. Geological Survey
Updater 01-AUG-91 Peterson, Jocelyn A. U.S. Geological Survey