Mt. Eolus Mine

The Mt. Eolus Mine is a silver mine located in La Plata county, Colorado at an elevation of 11,759 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: Mt. Eolus Mine

Commodity

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

Location

State: Colorado
County: La Plata
District: Needle Mountain (Tacoma, Florida, Vallecito) 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.
Administrative Organization: San Juan N. F.

Holdings

Not available

Workings

Not available

Ownership

Not available

Production

Not available

Deposit

Record Type: Site
Operation Category: Occurrence
Deposit Type: Vein
Operation Type: Unknown
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: Polymetallic veins

Orebody

Not available

Structure

Type: R
Description: San Juan Uplift, San Juan Basin, San Juan Volcanic Field

Type: L
Description: Needle Mtns Uplift, Chicago Basin Stock, Eolus Batholith, Trimble Stock

Alterations

Not available

Rocks

Name: Rhyolite
Role: Associated
Age Type: Associated Rock Unit
Age in Years: 10.100000+-1.100000
Material Analyzed: Zircon
Age Young: Miocene

Name: Rhyolite
Role: Associated
Age Type: Associated Rock Unit
Age in Years: 9.000000+-0.900000
Material Analyzed: Zircon
Age Young: Miocene

Name: Granite
Role: Associated
Age Type: Associated Rock Unit
Age in Years: 10.100000+-1.100000
Material Analyzed: Zircon
Age Young: Miocene

Name: Granite
Role: Associated
Age Type: Host Rock Unit
Age in Years: 1460.000000+-70.000000
Dating Method: K-Ar
Age Young: Precambrian

Name: Granite
Role: Associated
Age Type: Associated Rock Unit
Age in Years: 9.000000+-0.900000
Material Analyzed: Zircon
Age Young: Miocene

Name: Granite
Role: Associated
Age Type: Associated Rock Unit
Age in Years: 1466.000000+-20.000000
Dating Method: U-Pb (zircon)
Material Analyzed: Zircon
Age Young: Precambrian

Name: Granite
Role: Associated
Age Type: Associated Rock Unit
Age in Years: 1466.000000+-27.000000
Dating Method: Rb-Sr
Age Young: Precambrian

Name: Granite
Role: Host
Age Type: Associated Rock Unit
Age in Years: 1466.000000+-20.000000
Dating Method: U-Pb (zircon)
Material Analyzed: Zircon
Age Young: Precambrian

Name: Granite
Role: Host
Age Type: Associated Rock Unit
Age in Years: 10.100000+-1.100000
Material Analyzed: Zircon
Age Young: Miocene

Name: Granite
Role: Host
Age Type: Associated Rock Unit
Age in Years: 1466.000000+-27.000000
Dating Method: Rb-Sr
Age Young: Precambrian

Name: Granite
Role: Host
Age Type: Associated Rock Unit
Age in Years: 9.000000+-0.900000
Material Analyzed: Zircon
Age Young: Miocene

Name: Granite
Role: Host
Age Type: Host Rock Unit
Age in Years: 1460.000000+-70.000000
Dating Method: K-Ar
Age Young: Precambrian

Name: Quartz Monzonite
Role: Host
Age Type: Host Rock Unit
Age in Years: 1466.000000+-20.000000
Dating Method: U-Pb (zircon)
Material Analyzed: Zircon
Age Young: Precambrian

Name: Quartz Monzonite
Role: Host
Age Type: Host Rock Unit
Age in Years: 1460.000000+-70.000000
Dating Method: K-Ar
Age Young: Precambrian

Name: Quartz Monzonite
Role: Host
Age Type: Host Rock Unit
Age in Years: 1466.000000+-27.000000
Dating Method: Rb-Sr
Age Young: Precambrian

Name: Quartz Monzonite
Role: Host
Age Type: Associated Rock Unit
Age in Years: 9.000000+-0.900000
Material Analyzed: Zircon
Age Young: Miocene

Name: Quartz Monzonite
Role: Host
Age Type: Associated Rock Unit
Age in Years: 10.100000+-1.100000
Material Analyzed: Zircon
Age Young: Miocene

Name: Quartz Monzonite
Role: Associated
Age Type: Associated Rock Unit
Age in Years: 9.000000+-0.900000
Material Analyzed: Zircon
Age Young: Miocene

Name: Quartz Monzonite
Role: Associated
Age Type: Host Rock Unit
Age in Years: 1460.000000+-70.000000
Dating Method: K-Ar
Age Young: Precambrian

Name: Quartz Monzonite
Role: Associated
Age Type: Host Rock Unit
Age in Years: 1466.000000+-27.000000
Dating Method: Rb-Sr
Age Young: Precambrian

Name: Quartz Monzonite
Role: Associated
Age Type: Host Rock Unit
Age in Years: 1466.000000+-20.000000
Dating Method: U-Pb (zircon)
Material Analyzed: Zircon
Age Young: Precambrian

Name: Quartz Monzonite
Role: Associated
Age Type: Associated Rock Unit
Age in Years: 10.100000+-1.100000
Material Analyzed: Zircon
Age Young: Miocene

Analytical Data

Analytical Data: CHEMICAL ANALYSES SHOWED LT 0.02 AND 0.08 PPM AU, 10 AND 430 PPM CU, 30 AND 190 PPM PB, 40 AND 200 PPM ZN.
Analytical Data: STEVEN AND OTHERS' (1969) SAMPLE OF QUARTZ VEIN AT FACE OF UPPER DRIFT CONTAINED TRACE AU, 3.52 OZ/TON AG, TRACES OF CU, PB, AND ZN. SEMIQUANTITATIVE SPECTROGRAPHIC ANSLYSES OF TWO SAMPLES OF QUARTZ VEIN MATERIAL CONTAINED 50 AND 2000 PPM TI, 500 AND GT 5000 PPM MN, 7 AND 50 PPM AG, LT 200 PPM AS, 70 AND 1000 PPM BA, LT 10 PPM BI, LT 20 PPM CD, LT 5AND 5 PPM CR, LT 5 AND 300 PPM MO, 100 AND 300 PPM PB, LT 100 PPM SB, LT 10 PPM SN, LT 100 AND 500 PPM SR, 10 AND 50 PPM V, LT 50 PPM W, LT 200 PPM ZN

Materials

Ore: Sphalerite
Gangue: Quartz
Gangue: Calcite
Gangue: Rhodochrosite
Gangue: Fluorite

Comments

Comment (Deposit): MINE DEVELOPED ON TWO VEINS TRENDING N 50 W AND N 65 E, 83 NW, BOTH IN THE EAST-WEST-TRENDING FRACTURES OF THE REGIONAL RECTANGULAR SYSTEM

Comment (Workings): UPPER TUNNEL IS 265-FT DRIFT ON VEIN TRENDING N 65 E; LOWER TUNNEL IS CROSSCUT OF UNKNOWN EXTENT

Comment (Location): (LAND STATUS AND ADMINISTRATIVE AREA LOCATIONS CALCULATED USING GIS OVERLAY ANALYSIS FOR SAN JUAN N. F.). AT SE BASE OF MT EOLUS AT HEAD OF CHICAGO BASIN 1.3 MILES NW OF COLUMBINE PASS. ; INFO FROM LAND.ST :1974

Comment (Commodity): PRINCIPAL ORE MINERALS LISTED ARE BASED ON LIST FOR DISTRICT. OCCURENCE OF OTHER AG AND CU SULFIDES UNVERIFIED.

References

Reference (Deposit): SCHMITT, L.J., AND RAYMOND, W.H., 1977, GEOLOGY AND MINERAL DEPOSITS OF THE NEEDLE MOUNTAINS DISTRICT, SOUTHWESTERN COLORADO: USGS BULL. 1434, 40 P.

Reference (Deposit): STEVEN, T.A., AND OTHERS, 1969, MINERAL RESOURCES OF THE SAN JUAN PRIMITIVE AREA, COLORADO: USGS BULL. 1261-F, P. 30-32, 55-67, 94, 162-163.

Reference (Deposit): CROSS, WHITMAN, AND OTHERS, 1905, DESCRIPTION OF THE NEEDLE MOUNTAINS QUADRANGLE, COLORADO: USGS FOLIO 131.

Colorado Mining Photos

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