Mouat-Sampson

Site Name

Primary: Mouat-Sampson
Secondary: Mouat
Secondary: Mountain View Mine
Secondary: Mouat Mine

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Commodity

Primary: Chromium
Secondary: Palladium
Secondary: Platinum
Secondary: Rhodium

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Location

State: Montana
County: Stillwater
District: Stillwater

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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.

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Holdings

Type: Patented

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Workings

Type: Underground

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Ownership

Owner Name: Boulder Gold N. L.
Home Office: Colorado
Info Year: 1993

Owner Name: Chrome Corp. Of America
Percent: 100.0
Home Office: Colorado
Info Year: 1993

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Production

Year: 1962
Time Period: 1943-1962
Mined: 1906000.000 mt
Material type: ore

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Deposit

Record Type: Site
Operation Category: Past Producer
Deposit Type: Stillwater Ni-Cu
Operation Type: Underground
Mining Method: Unknown
Milling Method: Gravity
Year First Production: 1943
Discovery Year: 1886
Years of Production:
Organization:
Significant: Y

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Physiography

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

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Mineral Deposit Model

Model Name: Stillwater Ni-Cu

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Orebody

Form: MASSIVE BAND, DISSEMINATED

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Structure

Type: L
Structure: LAKE FAULT (N72W, DIP 60SW), CLIFF FAULT (N75W, DIP 70SW)

Type: R
Structure: BEARTOOTH UPLIFT

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Alterations

Alteration Type: L
Alteration: MINOR SERPENTINIZATION OF HARZBURGITE

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Rocks

Name: Quartz Monzonite
Role: Associated
Description: QUARTZ MONZONITE
Age Type: Associated Rock
Age Young: Neoarchean

Name: Harzburgite
Role: Host
Description: HARZBURGITE
Age Type: Host Rock
Age Young: Neoarchean

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Analytical Data

Not available

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Materials

Ore: Chromite
Ore: Bronzite
Gangue: Olivine
Unknown: Forsterite
Unknown: Enstatite

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Comments

Comment (Geology): 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) ; REG.TRENDS: STRIKE OF ULTRAMAFIC ZONE: N 60 DEG.W -N 80 DEG. W

Comment (Geology): THE LARGEST POTENTIAL RESOURCES OF CHROMIUM AND PGE IN THE U.S. OCCUR IN THE STILLWATER COMPLEX. AGE OF STILLWATER COMPLEX IS 2,705 +/- 4 MA BASED ON U-PB SYSTEMATICS ON ZIRCON-BADDELEYITE (PREMO AND OTHERS, 1990) ; GEOL.DESC: AGE OF HOST ROCKS: PRE-CAMBRIAN; MAJOR.UNITS: STILLWATER COMPLEX

Comment (Deposit): MAJOR ORE DEPOSITS IN "G" AND "H" CHROMITITE ZONES OF PERIDOTITE MEMBER OF STILLWATER COMPLEX . "G" BAND AVERAGES 16 FT THICK, 21.5% CR2O3; "H" AVERAGES 5.8 FT THICK, 22.1% CR2O3. DEPOSIT IS CUT BY LAKE AND CLIFF FAULTS

Comment (Geology): 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 THAT 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

Comment (Geology): CR:FE RATIO APPROX 1.7:1 ANALYSIS OF THE MOUAT MINERAL CHROMITE IS: 44.3 PERCENT CHROMIC OXIDE 17.6 PERCENT IRON 20.6 PERCENT ALUMINA 12.8 PERCENT MAGNESIA 0.7 PERCENT SILICA 0.7 PERCENT CALCIUM OXIDE

Comment (Names): OTHER NAME: MOUAT-SAMPSON. PART OF STILLWATER COMPLEX

Comment (Reserve-Resource): GRADE IS REPRESENTATIVE OF MINE DILUTION CR:FE RATIO APPROX 1.7:1

Comment (Deposit): ORE BODY TYPE IS ORIGINAL ROCK FORMER (A MAGMATIC DIFFERENTIATE). THE MOUAT MINE CONSISTS OF TWO PARALLEL ORE BODIES OR ZONES, THE G & THE H. THESE ZONES OR LAYERS ARE MINED SIMULTANEOUSLY. THE G LAYER AVERAGES 2.7M. (9FT) THICK AND THE H LAYER 1.7M (5.5FT) THICK. TYPE OF WALL ROCK ALTERATION IS SERPENTINIZATION.

Comment (Workings): UNDERGROUND MINING IS EXPECTED TO RESULTS IN MINIMAL SURFACE DISTURBANCE. SURFACE FACILITIES WOULD LIKELY BE RESTRICTED TO PREVIOUS MINE SITES, ROADS, ETC. MINE ROAD DISTANCE IS 8KM. WATER SUPPLY DISTANCE IS 5KM. ELECTRICAL SUPPLY SOURCE IS 21KM.

Comment (Reserve-Resource): DEPOSIT REPORT. UPDATED IN 1987/88 --COSTING INCLUDED FECR SMELTER CONSTRUCTION IN COLUMBUS, MONT. 1993 RESERVES FROM RANDOL 1993/94.

Comment (Economic Factors): DEVELOPMENT AND PRODUCTION HISTORY OF MOUAT MINE AS REPORTED BY THE AMERICAN CHROME COMPANY (OPERATOR FROM 1953 TO 1961): 1941-1943 DEVELOPMENT- UNDERGROUND, 11783 METERS PRODUCTION - MINED, 166200 TONNES AT 21.64 PERCENT CR2O3 MILLED, 70,485 TONNES AT 19.26 PERCENT CR2O3 CONCENTRATES, 26,796 TONNES AT 38.81 PERCENT CR2O3 1953-1961 DEVELOPMENT- UNDERGROUND, 18,382 METERS PRODUCTION - CONCENTRATES, 860,000 TONNES AT 38.57 PERCENT CR2O3

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References

Reference (Production): NORTHWEST CHROMITE ORES. U.S. BUR OF MINES R.I. 5646, 1969

Reference (Production): BENEFICIATION OF OFF-GRADE CHROMITE AND PRODUCTION OF FER-

Reference (Production): CHEMICAL BENEFICIATION OF CHROMITE ORES. U.S. BUR OF MINES

Reference (Deposit): WIMMLER, N.L. INVESTIGATION OF CHROMITE DEPOSITS OF THE

Reference (Deposit): SCHAFER, P.A. CHROMITE DEPOSITS OF MONTANA. MONTANA BUR. OF

Reference (Deposit): JACKSON, E.D. THE CHROMITE DEPOSITS OF THE STILLWATER COM-

Reference (Production): GRADE CHROMITES FROM THE STILLWATER COMPLEX, MONTANA. U.S.

Reference (Deposit): STILLWATER COMPLEX, STILLWATER AND SWEETGRASS COUNTIES,

Reference (Deposit): MINES AND GEOL. MEM. 18, 1937, 35 PP.

Reference (Deposit): U.S. GEOLOGICAL SURVEY OPEN FILE RPT., 1954, 2 MAPS, 8 SECTIONS

Reference (Deposit): MOUNTAIN VIEW LAKE AREA, STILLWATER COUNTY, MONTANA,

Reference (Deposit): GEOLOGIC MAP, SECTIONS, AND UNDERGROUND WORKINGS OF THE

Reference (Deposit): PEOPLES, J.W., A.L. HOWLAND, W.R. JONES, AND D. FLINT.

Reference (Deposit): MONTANA. U.S. GEOLOGICAL SURVEY BULL. 922-N, 1940, PP. 371-416.

Reference (Deposit): (GRATON SALES), V. 2. NEW YORK, AIME, 1968, PP. 1495-1510.

Reference (Deposit): AMER. MEM. 80, 1960, 230 PP.

Reference (Deposit): PLEX, MONTANA. IN ORE DEPOSITS IN THE U.S., 1933-1967,

Reference (Deposit): HESS, H.H. STILLWATER IGNEOUS COMPLEX, MONTANA. GEOL. SOC.

Reference (Deposit): 1962, 96 PP.

Reference (Deposit): ANONYMOUS. CHROMIUM MATERIALS SURVEY. U.S. DEPT. COMMERCE,

Reference (Reserve-Resource): MINES I.C. 8204, 1963, 58 PP.

Reference (Reserve-Resource): CHROME COMPANY, STILLWATER COUNTY, MONTANA. U.S. BUR OF

Reference (Reserve-Resource): PRICE, P.M. MINING METHODS AND COSTS, MOUAT MINE, AMERICAN

Reference (Reserve-Resource): 9 PP.

Reference (Reserve-Resource): SOUTHWESTERN MONTANA. U.A. GEOLOGICAL SURVEY CIRC. 684, 1973,

Reference (Geology): THE STILLWATER COMPLEX IN STILLWATER COUNTY, MONTANA. U.S.

Reference (Geology): GEOLOGICAL MAPS AND SECTIONS OF THE EASTERN PART OF

Reference (Geology): JACKSON, E.D., A.L. HOWLAND, J.W. PEOPLES, AND W.R. JONES.

Reference (Geology): TECTONIC STRUCTURE OF THE STILLWATER COMPLEX, MONTANA.

Reference (Geology): JONES, W.R., J.W. PEOPLES, AND A.L. HOWLAND. IGNEOUS AND

Reference (Geology): GEOLOGICAL SURVEY OPEN FILE RPT., 1954, 3 MAPS, 14 SECTIONS.

Reference (Reserve-Resource): PAGE, N.J., AND J.C. DOHRENWEND. MINERAL RESOURCE POTEN-

Reference (Geology): AMER. SPEC. PAPER 1, 1963, PP. 46-54.

Reference (Geology): MITE COMPOSITION IN THE STILLWATER COMPLEX. MIN. SOC.

Reference (Geology): JACKSON, E.D. STRATIGRAPHIC AND LATERAL VARIATION OF CHRO-

Reference (Geology): U.S. GEOLOGICAL SURVEY PROF. PAPER 358, 1961, 106 PP.

Reference (Geology): THE ULTRAMAFIC ZONE OF THE STILLWATER COMPLEX, MONTANA.

Reference (Geology): JACKSON, E.D. PRIMARY TEXTURES AND MINERAL ASSOCIATIONS IN

Reference (Production): BUR OF MINES R.I. 6448, 1964, 29 PP.

Reference (Production): SULLIVAN, F.V. AND G.F. WORKENTINE. BENEFICIATING LOW-

Reference (Production): 14 PP.

Reference (Production): SULLIVAN, F.V. AND W.A. STICKNEY. FLOTATION OF PACIFIC

Reference (Production): ROCHROMIUM. U.S. BUR OF MINES R.I. 6010, 1962, 16 PP.

Reference (Deposit): PEOPLES, J.W., AND A.L. HOWLAND. CHROMITE DEPOSITS OF THE

Reference (Production): HUNTER, WILLARD L. AND LLOYD H. BANNING. PYROMETALLURGICAL

Reference (Production): R.I. 3817, 1945, 26 PP.

Reference (Production): BOERICKE, F.S. AND W.M. BANGERT. EFFECT OF VARIABLES IN

Reference (Deposit): MCHUGH, 1994, MLA REPORT IN PREPARATION.

Reference (Geology): U.S. GEOLOGICAL SURVEY BULL. 1071-H, 1960, PP. 281-340.

Reference (Deposit): MONTANA. U.S. BUR. OF MINES R.I. 4368, 1948, 41 PP.

Reference (Deposit): EASTERN PART OF THE STILLWATER COMPLEX, STILLWATER COUNTY,

Reference (Reserve-Resource): NORTHERN PART OF THE MT. WOOD AND MT. DOUGLAS QUADRANGLES,

Reference (Reserve-Resource): TIAL OF THE STILLWATER COMPLEX AND ADJACENT ROCKS IN THE

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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.