Valley Forge Mine

The Valley Forge Mine is a gold, silver, and lead mine located in Lewis and Clark 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

Name: Valley Forge Mine  

State:  Montana

County:  Lewis and Clark

Elevation:

Primary Mineral: Gold, Silver, Lead

Lat, Long: 46.49167, -112.24028

Map: View on Google Maps

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.


Satelite image of the Valley Forge Mine

Valley Forge Mine MRDS details

Site Name

Primary: Valley Forge Mine


Commodity

Primary: Gold
Primary: Silver
Primary: Lead
Secondary: Zinc
Secondary: Copper
Tertiary: Arsenic


Location

State: Montana
County: Lewis and Clark
District: Rimini District


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.


Holdings

Not available


Workings

Type: Underground


Ownership

Not available


Production

Not available


Deposit

Record Type: Site
Operation Category: Past Producer
Operation Type: Unknown
Year First Production: 1885
Years of Production:
Organization:
Significant: N
Deposit Size: S


Physiography

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


Mineral Deposit Model

Not available


Orebody

Not available


Structure

Type: R
Description: Boulder Batholith

Type: L
Description: Lee Mountain-Valley Forge Shear Zone


Alterations

Alteration Type: L
Alteration Text: Sericitization


Rocks

Name: Quartz Monzonite
Role: Associated
Age Type: Associated Rock Unit
Age Young: Late Cretaceous

Name: Quartz Monzonite
Role: Associated
Age Type: Host Rock
Age Young: Late Cretaceous

Name: Quartz Monzonite
Role: Associated
Age Type: Associated Rock
Age Young: Late Cretaceous


Analytical Data

Analytical Data: ORE $6/TON AU, 12 OZ/TON AG, 7% PB. HIGHER GRADE ORE SAID TO CARRY $11/TON AU.


Materials

Ore: Gold
Ore: Galena
Ore: Sphalerite
Ore: Chalcopyrite
Gangue: Quartz
Gangue: Tourmaline
Gangue: Pyrite


Comments

Comment (Deposit): 2 ORE BODIES; EAST BODY IS 300 FT. LONG AND WORKED TO A DEPTH OF 200 FT., WEST ORE BODY IS 350 FT. LONG AND EXTENDS BELOW 600 FOOT LEVEL (200-300 FT. BELOW MIDDLE ADIT)

Comment (Workings): ORE BINS NEAR LOWER MOST TUNNEL (5,500 FT.) CONNECTED TO RAILWAY BY AN AERIAL TRAMWAY (1911). MINE CONSISTS OF 2 CAVED SHAFTS, 2 ADITS WEST OF THE SHAFTS, A 2,000 FT. CROSSCUT FROM RIMINI, A RAISE, AND LEVELS AT 100 FOOT INTERVALS

Comment (Geology): VEIN OF JASPEROID 200 FT. SOUTH OF VALLEY FORGE LODE SAID TO CONTAIN GOLD.

Comment (Location): 1000 FT HIGHER THAN RIMINI. ; INFO FROM LAND.ST :(1950)

Comment (Production): $200,000 IN AU, AG, PB ORE PRODUCED PRIOR TO 1911. SEVERAL THOUSANDS TONS OF ORE BETWEEN 1914 AND 1919.


References

Reference (Deposit): USGS BULL 527, P. 82-3.

Reference (Deposit): USGS BULL 842, P. 257-58.

Reference (Deposit): USGS PP 428, P. 55, PL. 1.

Reference (Production): USGS PP 428, P. 55; USGS BULL 842, P. 257.