The Sierra Mine is a copper mine located in Granite 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.
Sierra Mine MRDS details
Site Name
Primary: Sierra Mine
Commodity
Primary: Copper
Secondary: Silver
Secondary: Gold
Tertiary: Antimony
Location
State: Montana
County: Granite
District: Garnet (First Chance) District
Land Status
Not available
Holdings
Not available
Workings
Type: Underground
Ownership
Not available
Production
Not available
Deposit
Record Type: Site
Operation Category: Past Producer
Operation Type: Unknown
Years of Production:
Organization:
Significant: N
Deposit Size: S
Physiography
General Physiographic Area: Rocky Mountain System
Physiographic Province: Northern Rocky Mountains
Physiographic Detail: Garnet Range
Mineral Deposit Model
Not available
Orebody
Not available
Structure
Type: R
Description: Bearmouth Overthrust
Type: L
Description: Deep Creek Anticline, Garnet Stock
Alterations
Alteration Type: L
Alteration Text: Oxidation
Rocks
Name: Diorite
Role: Associated
Age Type: Host Rock
Age Young: Late Cretaceous
Name: Diorite
Role: Associated
Age Type: Associated Rock Unit
Age Young: Late Cretaceous
Name: Diorite
Role: Associated
Age Type: Associated Rock
Age Young: Late Cretaceous
Analytical Data
Not available
Materials
Ore: Gold
Ore: Tetrahedrite
Gangue: Ankerite
Gangue: Quartz
Gangue: Limonite
Gangue: Pyrite
Gangue: Calcite
Comments
Comment (Production): SMALL PRODUCTION OF MEDIUM GRADE ORE PRE1916
Comment (Deposit): VEIN EXTENDS AT LEAST 500 FT HORIZONTALLY BUT PINCHES OUT AT DEPTH.
Comment (Location): Political location in record is Granite county. The MRDS location-problem GIS test indicated the lat/long fell in adjacent Missoula county. However, the topo sheet, Google Earth, and County100 coverage plot it 520m inside Granite county. No change is necessary.
References
Reference (Production): USGS BULL 660, P. 187
Reference (Deposit): USGS BULL 660, P. 171-82, 187
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.
