Needle Mountain District

The Needle Mountain District is a gold and silver mine located in La Plata county, Colorado.

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: Needle Mountain District
Secondary: Tacoma District

Commodity

Primary: Gold
Primary: Silver
Secondary: Copper
Secondary: Lead
Tertiary: Manganese
Tertiary: Molybdenum
Tertiary: Uranium
Tertiary: Antimony
Tertiary: Zinc
Tertiary: Bismuth

Location

State: Colorado
County: La Plata
District: TACOMA DISTRICT

Land Status

Not available

Holdings

Not available

Workings

Not available

Ownership

Not available

Production

Not available

Deposit

Record Type: District
Operation Category: Past Producer
Deposit Type: VEIN, DISSEMINATION, REPLACEMENT
Operation Type: Unknown
Year First Production: 1880
Year Last Production: 1936
Discovery Year: 1880
Years of Production:
Organization:
Significant:

Physiography

Not available

Mineral Deposit Model

Model Name: Replacement Mn

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

Alteration Type: L
Alteration: HYDROTHERMAL
Alteration Text: CHICAGO BASIN STOCK SHOWS ALTERATION RELATED TO THREE SEPARATE PERIODS OF HYDROTHERMAL ACTIVITY. OLDER PART OF PORPHYRY IS FE-STAINED, BLEACHED, SILICIFIED ROCK CHARACTERIZED BY DISSEMINATED PYRITE-MO AND QUARTZ-SERICITE OR QUARTZ-SERICITE-KAOLINITE ASSEMBLAGES IN NETWORKS AND COARSE-GRAINED AGGREGATES. SERICITIZATION MORE INTENSE IN WEST PART OF STOCK. DICKITE-PYROPHYLLITE OF ADVANCED ARGILLIC ASSEMBLAGE IN EASTERN PART SUGGESTS LOCALLY INTENSE HYDROLYTIC ACTIVITY IN WHICHPYROPHYLLITE REPLACED SERICITE. PRIMARY SERICITE HALO IN EOLUS GRANITE AROUND EDGE OF OLDER PART OF STOCK. ALTERATION PHASE LARGELY COMPLETED BEFORE INTRUSION OF INNER YOUNGER PORPHYRY, WHICH CONTAIN INCLUSIONS OF OLDER ALTERED PORPHYRY BUT WHICH ITSELF SHOWS LESS INTENSE ALTERATION--WEAK AND IRREGULAR PLAGIOCLASE REPLACEMENT BY SERICITE, BIOTITE ALTERATION TO CHLORITE, RUTILE, AND SERICITE, LOCALLY INTENSE ARGILLIZATION, MOST COMPLETE AT OUTER MARGINS. LATER MAFIC DIKE CUTTING BOTH PORPHYRIES SHOWS CHOLRITIZED DIOPSIDE AND CLINOPYROXENE. UPPER PARTS OF METALLIFEROUS VEINS SHOW OXIDATION OF RHODOCHROSITE TO MN OXIDES, SUPERGENE ALTERATION OF SULFIDES (CHALCOPYRITE TO AZURITE, MALACHITE, COVELLITE; SPHALERITE TO HYDROZINCITE; GALENA TO ANGLESITE).

Rocks

Not available

Analytical Data

Not available

Materials

Not available

Comments

Not available

References

Reference (Deposit): TRIPPE, T.M., 1905, REPORT ON THE AETNA MINE ACCOMPANIED BY A STATEMENT CONCERNING THE ADJOINING AZTEC AND REPUBLIC CLAIMS, LA PLATA COUNTY: COLO. DIV. MINES FILES, UNPIB. ENG. REPT., 3 P.

Reference (Deposit): COLORADO DIV. MINES INF. REPT. (BROOKLYN GROUP).

Reference (Deposit): BLM MINERAL SURVEYS

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

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

Reference (Deposit): BARKER, FRED, 1969, PRECAMBRIAN GEOLOGY OF THE NEEDLE MOUNTAINS, SOUTHWESTERN COLORADO: USGS PROF. PAPER 644-A. 35 P.

Reference (Deposit): STEVEN, T.A., AND OTHERS, 1969, MINERAL RESOURCES OF THE SAN JUAN PRIMITIVE AREA, COLORADO: USGS BULL. 1261-F.

Reference (Deposit): MUILENBURG, G.A., 1919, MANGANESE DEPOSITS OF COLORADO: CGS BULL. 15, P. 49.

Reference (Deposit): A WORCESTER, P.G., 1919, MOLYBDENUM DEPOSITS OF COLORADO WITH GENERAL NOTES ON THE MOLYBDENUM INDUSTRY: CGS BULL. 14, P. 68-69.

Reference (Deposit): LAKES, ARTHUR, 1897, THE NEEDLES--LA PLATA MOUNTAINS, COLLIERY ENGINEER, V. 18, P. 74-77, 101-103.

Colorado Mining Photos

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