Mouat Nickel-Copper Copper Occurrence
Nye, Montana
45.3768°N 109.8999°W
Mine Overview
The Mouat Nickel-Copper Copper Occurrence is near Nye, Montana. Historically the site has been associated with the Stillwater Mining District which is now part of the Custer National Forest. The site was first discovered in 1967. Ore mineralization has been found at this location and the size of the deposit is estimated to be small, however the precise grade, tonnage, and extent of the mineralization are not known. There has been no production and little to no activity other than routine claim maintenance since the mineral discovery. The ore mined is composed of pentlandite, pyrrhotite and chalcopyrite with waste material consisting primarily of olivine, plagioclase and magnetite. The ore body is described as tabular shaped of unknown dimensions. The mineralization at this location is from the Neoarchean era 2.80 to 2.50 billion years ago. The Middle Rocky Mountains physiographic province of the Rocky Mountain System characterize the geomorphology of the surrounding area.
Site identification and general characteristics. Learn about USGS mines.
Owner Name and Address
Anaconda Company
- Type
- Operator
Commodities
Additional textual information about a site or mine.
- Commodity Type Importance
- Copper Metallic Primary
- Nickel Metallic Primary
- Cobalt Metallic Secondary
- Gold Metallic Tertiary
- Platinum Group Elements (PGE) Metallic Tertiary
- Silver Metallic Tertiary
Deposit
ORE CONSISTS OF DISSEMINATED, MATRIX, AND MASSIVE CONCENTRATIONS OF MAGMATIC SULFIDES IN LENSES AND TABULAR BODIES IN MAFIC AND ULTRAMAFIC INTRUSIONS NEAR THE MARGIN OF THE STILLWATER COMPLEX. SULFIDE MINERALIZATION THAT CONSTITUTES THE MOUAT DEPOSIT LIES NEAR THE BASE OF THE STILLWATER COMPLEX WEST OF THE STILLWATER RIVER. THE HOST ROCKS LIE BETWEEN TWO SOUTH-DIPPING, HIGH-ANGLE REVERSE FAULTS, THE LAKE FAULT ON THE NORTH AND THE BLUEBIRD THRUST ON THE SOUTH. LAYERED ROCKS OF THE STILLWATER COMPLEX ARE FOLDED INTO A BROAD SYNCLINE BETWEEN THESE TWO FAULTA AND, IN THE AREA OF THE COPPER-NICKEL SULFIDE DEPOSITS, GENERALLY DIP 60 DEGREES NORTHWEST. BETWEEN THE TWO HIGH-ANGLE REVERSE FAULTS, THE DEPOSIT IS CUT BY AN OLDER SET OF FAULTS THAT STRIKE NORTHEAST AND HAVE NEAR VERTICAL DIPS AND A YOUNDER SET OF NORTHWEST-STRIKING, NEAR VERTICAL FAULTS THAT SHOW LEFT-LATERAL DISPLACEMENT. THE MOUAT DEPOSIT CAN BE SUBDIVIDED INTO TWO PARTS, A NORTHERN BLOCK THAT LIES NORTH OF VERDIGRIS CREEK (SEE.
RECORD M060102) AND A SOUTHERN PART THAT LIES SOUTH OF VERDIGRIS CREEK (THIS RECORD ). MINERALIZED ROCKS SOUTH OF VERDIGRIS CREEK ARE ALMOST COMPLETELY COVERED BY GLACIAL DEPOSITS; DRILLING HAS SHOWN THAT SULFIDE MINERALIZATION OCCURS BOTH IN THE BASAL SERIES (AND TO A LESSER EXTENT THE PERIDOTITE ZONE) OF THE STILLWATER COMPLEX AND IN STILLWATER-ASSOCIATED SILLS AND DIKES THAT INTRUDE THE METAMORPHOSED SEDIMENTARY ROCKS BELOW THE BASE OF THE STILLWATER COMPLEX. THE MINERALIZED SILLS AND DIKES ARE LESS COMMON AND ARE SMALLER THAN THOSE IN THE AREA NORTH OF VERDIGRIS CREEK. SEE PAGE AND OTHERS (1985A ), PAGE AND NOKLEBERG (1974 ), ZIENTEK AND OTHERS (1989).
METALLURGICAL STUDIES BY ANACONDA INDICATED THAT BULK SULFIDE FLOTATION PRODUCED A LOW-GRADE CONCENTRATE WITH GOOD RECOVERY; HOWEVER, THIS CONCENTRATE WAS UNSUITABLE FOR SMELTER FEED AND WAS THEREFORE UNSALABLE. A LARGE PROPORTION OF THE NICKEL IS ASSOCIATED WITH PYRRHOTITE, EITHER IN SOLID SOLUTION OR AS FLAME EXSOLUTION OF PENTLANDITE IN PYRRHOTITE.; INFORMATION SOURCE: 1 PUBLIC LITERATURE; 2 UNPUBLISHED REPORTS.
Location Info
- Stillwater , Montana County / State
- Continent Country State County
- North America The United States Montana Stillwater
Notes
UNSURVEYED
Development
THIS PART OF ORE EXTENSION OF THE MOUAT DEPOSIT WAS NOT DISCOVERED UNTIL 1967. EXPLORATION HISTORY IS SUMMARIZED IN PAGE AND OTHERS (1985B) AND OTHER SOURCES CITED BELOW. MINERALIZATION IN THE MOUAT DEPOSIT NORTH OF VERDIGRIS CRFEEK WAS DISCOVERED IN 1883 AND ALL EXPLORATION AND DEVELOPMENT WORK FOCUSSED ON THAT PART OF THE DEPOSIT. IT WAS NOT UNTIL THE 1960'S WHEN ANACONDA DECIDED TO RE-EVALUATE THE MOUAT AND ADJACENT AREAS FOR LARGE-TONNAGE LOW-GRADE DEPOSITS OF NICKEL-COPPER ORE, THAT WORK BEGAN IN THE SOUTH MOUAT AREA. INITIAL STUDIES BEGAN IN 1966; FULL-SCALE PROJECT WORK CONCENTRATING ON THE MOUAT AREA BEGAN IN MAY, 1967. THIS WORK EXTENDED THE AREA OF KNOWN MINERALIZATION TO THE SOUTH MOUAT AREA AND IDENTIFIED SEVERAL LARGE ANOMALOUS ZONES IN ADJACENT AREAS (GEOCHEMISTRY AND GEOPHYSICS ). DRILLING IN THE MOUAT AREA BEGAN IN SEPT. 1967. BY OCT. 1970, WHEN EXPLORATORY AND DEVELOPMENT DRILLING WAS CURTAILED, APPROX. 92, 0401 FEET OF CORE FROM 95 HOLES HAD BEEN DRILLED IN THE MOUAT AREA.
BOTH THE VERDIGRIS CREEK AND SOUTH MOUAT AREAS ). ALTHOUGH WORK CONTINUED SPORADICALLY IN THE VERDIGRIS CREEK AREA, NO WORK HAS BEEN DONE ON THE SOUTH MOUAT AREA SINCE 1970.
Workings
THERE ARE NO WORKINGS IN THE PART OF THE MOUAT DEPOSIT SOUTH OF VERDIGRIS CREEK.
Concentration Process
Processes that concentrated or enriched the mineralization of the mine.
- Concentration Process
- Magmatic Segregation, Liquid Immiscibility
Geology
AGE OF STILLWATER COMPLEX IS 2, 705 =/-4 MA BASED ON U-LEAD SYSTEMATICS ON ZIRCON-BADDELEYITE (PREMO AND OTHERS, 1991).
Orebody
Characteristics of the ore body.
Rocks
Geological materials at the site.
- Class? 1st Order Name? 2nd Order Name? 3rd Order Name? 4th Order Name? Most Specific Name? Begin Time End Time Description?
- Host Rock Stillwater Complex, Ultramafic Series, Peridotite Zone; Stillwater Complex, Basal Series; Stillwater Complex Plutonic Rock Ultramafic Intrusive Rock Peridotite Peridotite - - -
- Mineralization - - - - - Neoarchean Neoarchean -
Structure
Geologic structural features affecting or characterizing the site or mine.
- Scale Description
- Local See Deposit Description
- 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)
Tectonic
Tectonic setting in which the site or deposit is situated.
- Setting?
- The Tectonic Setting At Time Of Emplacement Of The Stillwater Complex Is Unknown- The Complex Was Emplaced Shortly After A Major, Regional Subduction-Related Magmatic Event Which Culminated In Emplacement Of The 2-73-2-79 Ga Granitoid Suite In The Batholith Exposed In The Beartooth Uplift (wooden And Others, 1991)- However, There Is No Evidence That The Magmatism That Formed The Stillwater Complex Is Related To Convergent Margin Tectonics And Magmatism
Physiography
Physiographic area where the resource is found.
- Division Province? Section
- Rocky Mountain System Middle Rocky Mountains -
Alteration
Mineralogical and chemical alteration at or near the site, which may help to indicate the geographic extent of the geological processes producing the mine.
- Type? Alterations
- Local None Related To The Ore-Forming Process
Analytical Data
Results of chemical or mineralogical analysis on materials at or near the site
- Line? Analysis Data?
- 1 SEE RESERVE/RESOURCE DATA. MEDIAN (AND MAXIMUM) PT, PD, AND RH CONTENTS IN PPB OF DIFFERENT ORE TYPES WITHIN THE MOUAT DEPOSIT (ZIENTEK AND OTHERS, 1986
- 2 ZIENTEK, 1993
- 3 UNPUB DATA): BASAL SERIES: DISSEMINATED ORE PLATINUM = 7.15 (140), PD=15 (78), RHODIUM = 1 (2)
- 4 NET-TEXTURED ORE PLATINUM = 3.3 (62), PD=13 (83), RHODIUM = 8.1 (18). STILLWATER-ASSOCIATED SILLS AND DIKES (MAFIC NORITE): DISSEMINATED ORE PLATINUM = 7.55 (24), PD=7.5 (18), RHODIUM = 0.6 (7)
- 5 NET-TEXTURED ORE PLATINUM = 4.2 (49), PD=14.5 (130), RHODIUM = 1 (9)
- 6 MASSIVE ORE PLATINUM = 3.05 (150), PD=22 (410), RHODIUM = 1.3 (9). STILLWATER-ASSOCIATED SILLS AND DIKES (GABBRONORITE): DISSEMINATED ORE PLATINUM = 5.0 (960), PD=9.2 (340), RHODIUM = 0.8 (5).
Ore Control
Controls on emplacement of ore such as faults or other structural features.
- Text?
- Immiscible Sulfide Liquid Enriched In Nickel And Copper 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)
Reserve-resource
RESOURCES BASED UPON EXPLORATION AND DEVELOPMENT DRILLING BY ANACONDA UP TO 1978 FOR THE ENTIRE MOUAT DEPOSIT (INCLUDES THE AREAS NORTH AND SOUTH OF VERDIGRIS CREEK. SEE ZINETEK (1993) FOR SUMMARY OF ADDITIONAL RESOURCE INFORMATION GENERATED BY ANACONDA (DIFFERENT CUT-OFF ). NOTE ON RESOURCE CALCULATION: FROM 1967-1970, ANACONDA DRILLED THE MOUAT DEPOSIT ON 200 FEET CENTERS AND USED A CORSS-SECTION METHOD TO CALCULATE RESOURCES. IN THE MID-1980'S, THE USGS UNSUCCESSFULLY ATTEMPTED TO STATISTICALLY ESTIMATE IN-SITU ORE RESERVES BY THE KRIGING TECHNIQUE; THE DRILL SPACING WAS NOT APPROPRIATE GIVEN THE COMPLEX DISTRIBUTION OF THE ORE.
Nearby Deposits
Other deposits in the same region.
-
Mouat Nickel-Copper Copper Prospect
- Copper commodity Site type Prospect status
- Stillwater, Montana
- 0.27 miles
-
Mouat Nickel-Copper Nickel Prospect
- Nickel commodity Site type Prospect status
- Stillwater, Montana
- 0.27 miles
-
Mountain View Cr-Pt Platinum Occurrence
- Chromium commodity Site type Occurrence status
- Stillwater, Montana
- 0.36 miles
-
Mouat Chromium Mine
- Chromium commodity Site type Mine status
- Stillwater, Montana
- Underground
- 0.66 miles
-
Mountain View Mine
- Chromium commodity Site type Mine status
- Stillwater, Montana
- Stillwater Nickel-Copper
- Underground
- 0.77 miles
-
Stillwater Pgm Mine
- Palladium commodity Site type Mine status
- Stillwater, Montana
- Platinum Group Elements Reef
- Beneficiation Mill
- (Flotation)
- Underground
- 1.22 miles
-
Nye Basin-Lip Chromium-Platinum Prospect
- Chromium commodity Site type Prospect status
- Stillwater, Montana
- Surface And Underground
- 2.05 miles
-
Dow Palladium Occurrence
- Palladium commodity Site type Occurrence status
- Sweet Grass, Montana
- 2.27 miles
-
Nye Basin Nickel-Copper Lip Copper Occurrence
- Copper commodity Site type Occurrence status
- Stillwater, Montana
- 2.28 miles
-
Initial Cr-Pt Platinum Occurrence
- Platinum commodity Site type Occurrence status
- Sweet Grass, Montana
- 2.34 miles
Nearby Mining Districts
- Stillwater Mining District (0 miles away)
Nearby Lands
- Custer National Forest (0 miles away)
- Absaroka-Beartooth Wilderness (1.16 miles away)
Footnotes
* Mine bounds on map indicate the general area that a mine occupies. For an detailed map, refer to the overseeing BLM field office.
** The mine central point is based on an average of the mine's bounding box(es) and does not necessarily fall on the claim itself.
1 World-class significance is determined by total endowment of the contained commodity. This includes all past production and remaining reserves. Each commodity is considered separately and commodities cannot be combined to arrive at a significant size. The tonnage thresholds are from the mine model grade-tonnage studies. As of June 2008, many entries were classified as significant under less strict rules.
Mining Claim News From The Diggings™
Learn more about the Bureau of Land Management, Public Land Survey System, and mining claims.
-
Understanding Claim Ownership
We receive lots of emails from people who find their name or a relative’s name on our site and want to know if this means they have some right to the land listed under that name.
-
Understanding BLM Administrative Areas
Whether it is filing a mine or researching one, the administering BLM office is going to be the definitive source.
-
Understanding Location Data
Mine handled by the Bureau of Land Management are not mapped by latitude and longitude, instead, these mines harken back to the Public Land Survey System.
-
Understanding Townships
A “township” can refer to two different things. Both are part of the PLSS measurement system but have different uses.
Notes
ANACONDA DID NOT ROUTINELY ANALYZE FOR METALS OTHER THAN COPPER AND NICKEL.