Brown's Lake

The Brown's Lake is a tungsten mine located in Beaverhead county, Montana.

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: Brown's Lake
Secondary: Ivanhoe
Secondary: Lost Creek
Secondary: Browns Lake Mine
Secondary: Lentung

Commodity

Primary: Tungsten
Secondary: Copper
Tertiary: Molybdenum

Location

State: Montana
County: Beaverhead
District: Lost Creek

Land Status

Land ownership: Mixed
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

Type: Surface/Underground

Ownership

Owner Name: General Electric

Owner Name: Garrand Corp.
Home Office: 10 Exchange Place, Salt Lake City, Utah

Owner Name: American Alloy Metals, Inc.

Production

Year: 1956
Time Period: 1952-56
Material type: ORE
Description: Cp_Grade: ^0.18% W03
Year: 1958
Time Period: 1953-58
Material type: ORE
Description: Cp_Grade: ^0.35% W03

Deposit

Record Type: Site
Operation Category: Past Producer
Deposit Type: Contact Metasomatic
Operation Type: Unknown
Year First Production: 1953
Year Last Production: 1958
Discovery Year: 1941
Years of Production:
Organization:
Significant: Y

Physiography

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

Mineral Deposit Model

Model Name: W skarn

Orebody

Form: TABULAR AND IRREGULAR

Structure

Type: L
Description: Contact Metamorphic Zone

Type: L
Structure: Pioneer Batholith

Alterations

Alteration Type: L
Alteration: Chloritization

Alteration Type: L
Alteration: Oxidation

Alteration Type: L
Alteration: Skarn

Rocks

Name: Granite
Role: Associated
Age Type: Host Rock
Age Young: Mississippian

Name: Granite
Role: Associated
Age Type: Associated Rock
Age Young: Late Permian

Analytical Data

Analytical Data: EASTERN ORE ZONE AVERAGES 0.59% WO3, WESTERN ORE ZONE AVERAGES 0.17% WO

Materials

Ore: Pyrrhotite
Ore: Malachite
Ore: Covellite
Ore: Bornite
Ore: Powellite
Ore: Scheelite
Ore: Chalcopyrite
Gangue: Epidote
Gangue: Magnetite
Gangue: Quartz
Gangue: Biotite
Gangue: Pyrite
Gangue: Garnet

Comments

Comment (Geology): FORMATION NAME IS AMSDEN. . MAJOR POST-ORE GEOLOGIC EVENT WAS NORMAL FAULTING.. LOCAL DEEP GLACIAL MORAINE COVER.

Comment (Reserve-Resource): "R" DENOTES IN SITU RESOURCES - QUANTITIES OF ECONOMIC INTEREST FOR THE NEXT FEW DECADES. "1" DENOTES KNOWN DEPOSITS WITH RELIABLE ESTIMATES. "E" DENOTES ECONOMICALLY EXPLOITABLE. "M" DENOTES MARGINALLY ECONOMIC. "2" DENOTES EXTENSIONS OF KNOWN DEPOSITS AND NEWLY DISCOVERED DEPOSITS - PRELIMINARY RESULTS. 1985 FIGURES COME FROM UNPUBLISHED PROPRIETARY INFORMATION. IN EXTENSION TO ORIGINAL ORE BODY, NOW LARGELY MINED OUT. PROBABLY EQUAL TO OR EXCEEDING PAST PRODUCTION.

Comment (Development): NATURE OF THE DISCOVERY WAS BY CONVENTIONAL PROSPECTING. NON-GEOLOGIC CONSTRAINTS ON DEVELOPMENT OR EXPANSION IN 1-5 YEARS WERE DUE TO THE MINE PLANT, PROCESSING, AND THE MARKET. KNOWN EXTENSION OF ORE BODY PROBABLY WILL BE DEVELOPED UNDER BETTER ECONOMIC CONDITIONS. PRODUCT UPGRADED BEFORE EXPORT: CONCENTRATE.

Comment (Location): POINT OF REFERENCE IS CENTROID; 100

Comment (Commodity): SCHEELITE CONTAINS APPRECIABLE POWELLITE

Comment (Workings): MINE DEVELOPED BY DRIFTS, RAISE, AND OPEN PIT

Comment (Deposit): DEPTH OF COVER: 0-60 FEET (APPROXIMATELY). DEPTH OF UNCONSOLIDATED COVER: 0-20 FEET

Comment (Deposit): AT WEST END OF CUT TWO ORE BODIES ARE SEPARATED BY BARREN MARBLE UP TO 16 FT. THICK. AT EAST END THE ORE BODIES ARE FAULTED TOGETHER. AN ISOLATED, 13-FT. THICK ORE BED IS 90-FT. STRATIGRAPHICALLY ABOVE THE MAIN ORE BODY.

Comment (Deposit): Discovery Year: ORIGINALLY LOCATED AS A COPPER PROPERTY

References

Reference (Deposit): GEACH, R.D., 1972, MINES AND MINERAL DEPOSITS (EXCEPT FUELS), BEAVERHEAD COUNTY, MONTANA, MONTANA BUREAU OF MINES AND GEOLOGY, BULLETIN 85, 194 P.

Reference (Deposit): DMEA 1951X

Reference (Deposit): DMEA 2292

Reference (Deposit): DMA-148

Reference (Production): DMEA FILES

Reference (Deposit): MYERS, W.B., 1952, GEOLOGY AND MINERAL DEPOSITS OF THE NORTHWEST QUARTER OF WILLIS QUADRANGLE AND ADJACENT BROWN'S LAKE AREA; BEAVERHEAD COUNTY, MONTANA, U.S. GEOLOGICAL SURVEY, OPEN FILE REPORT, P. 18.

Reference (Production): INTERNATIONAL STRATEGIC MINERALS INVENTORY RECORD W109

Reference (Deposit): PATTEE, E.C., 1960, TUNGSTEN RESOURCES OF MONTANA: DEPOSITS OF THE MOUNT TORREY BATHOLITH BEAVERHEAD COUNTY, U.S. BUREAU OF MINES, REPORT OF INVESTIGATION 5552, 41P.

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.