Twenty-Six Shafts

The Twenty-Six Shafts is a silver mine located in Custer county, Colorado at an elevation of 9,199 feet.

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: Twenty-Six Shafts
Secondary: Twenty-six-Polonia vein

Commodity

Primary: Silver
Secondary: Copper
Secondary: Lead

Location

State: Colorado
County: Custer
District: Rosita Hills District

Land Status

Land ownership: Private
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: Unknown

Ownership

Not available

Production

Not available

Deposit

Record Type: Site
Operation Category: Past Producer
Operation Type: Underground
Discovery Year: 1895
Discovery Method: Ore-Mineral In Place
Years of Production:
Organization:
Significant: N
Deposit Size: S

Physiography

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

Mineral Deposit Model

Model Name: Epithermal veins

Orebody

Not available

Structure

Type: R
Description: Rosita Volcanic Center, Wet Mtns

Type: L
Description: Twenty-Six Fault, Striking East-West

Alterations

Alteration Type: L
Alteration Text: Weak Argillization

Rocks

Not available

Analytical Data

Analytical Data: HIGH GRADE ORE 200-300 OZ/TON AG

Materials

Ore: Chalcopyrite
Ore: Argentite
Ore: Galena
Gangue: Calcite
Gangue: Pyrite
Gangue: Barite

Comments

Comment (Location): SOUTH SIDE OF DUTCH FLAT, 1 MILE NNE OF ROSITA, IN THE NW/4 SEC 28, T 22 S, R 71 W. INFO FROM LAND.ST :(1976)

Comment (Reserve-Resource): A 1981 report suggested that silver deposits may occur along this vein. (Sunshine files)

Comment (Workings): AT LEAST TWO SHAFTS; MAIN SHAFT ON WEST 130 FT (1896), NEWER SHAFT TO EAST 185 FT (1896); OTHER WORKINGS UNKNOWN

References

Reference (Deposit): EMMONS, S.F., 1896, THE MINES OF CUSTER COUNTY, COLORADO: USGS 17TH ANN. REPORT, PT 2, P. 405-472.

Reference (Deposit): SHARP, W.M., 1978, GEOLOGIC MAP OF THE SILVER CLIFF AND ROSITA VOLCANIC CENTERS, CUSTER COUNTY, COLORADO: USGS MAP I-1081.

Reference (Reserve-Resource): Sunshine Mining Co. Colorado exploration files, unpublished data, Colorado Geological Survey.

Reference (Deposit): CROSS, WHITMAN, 1896, GEOLOGY OF SILVER CLIFF AND THE ROSITA HILLS, COLORADO: USGS 17TH ANN. REPORT, PT 2, P. 263-403

Colorado Mining Photos

Check out this collection of Colorado's best historic mining photos: Incredible Photos of Colorado Mining Scenes.