Golconda Mine

The Golconda Mine is a gold and silver mine located in Rio Grande county, Colorado at an elevation of 11,946 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: Golconda Mine
Secondary: Golconda No. 1
Secondary: Golconda No. 2

Commodity

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

Location

State: Colorado
County: Rio Grande
District: Summit (Summitville) 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: Surface/Underground

Ownership

Not available

Production

Not available

Deposit

Record Type: Site
Operation Category: Past Producer
Operation Type: Unknown
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: Polymetallic veins

Orebody

Not available

Structure

Type: R
Description: San Juan Volcanic Field

Type: L
Description: Platoro Caldera, Summitville Caldera, Summitville Fault, South Mountain Dome

Alterations

Alteration Type: L
Alteration Text: Quartz-Alunite Solfataric Alteration

Rocks

Name: Quartz Latite
Role: Associated
Age Type: Associated Rock
Age Young: Miocene

Name: Quartz Latite
Role: Associated
Age Type: Host Rock
Age Young: Miocene

Analytical Data

Not available

Materials

Ore: Sphalerite
Ore: Galena
Gangue: Barite

Comments

Comment (Location): ON NE SLOPE OF SOUTH MTN 580 FT NW OF IOWA PORTAL. PORTAL NO. 2 ELEV FROM STEVEN AND RATTE (1960, PL. 4). ; INFO FROM LAND.ST :1975

Comment (Deposit): MINE DEVELOPED PRINCIPALLY ON BLACK WONDER (OR GOLCONDA) VEIN, MCDONALD VEIN, AND AZTEC VEIN, AND SECONDARILY ON TEWKSBURY VEIN, AZTEC VEIN IS OVAL PIPE IN HIGHLY SILICIFIED QUARTZ LATITE SURROUNDED BY ENVELOPE OF SOFT HIGHLY ARGILLIZED ALTERATION OVER TOP OF PIPE AT SE END. BETWEEN IOWA AND AZTEC 1 LEVELS, DEPOSIT IS CROSS-SHAPED AND SUGGESTS LOCALIZATION BY INTERSECTING FRACTURES. NORTH END OF AZTEC VEIN INTERSECTED BY N 50 TO 60 W TRENDING MCDONALD VEIN, AN IRREGULAR AND DISCONTINUOUS FRACTURE ZONE THAT ALSO INTERSECTS SOUTH END OF BLACK WONDER VEIN AND REFLECTS LOCALIZATION OF MINERALIZATION/ALTERATION BY INTERSECTION OF FRACTURES IN VEIN ZONE COMPLEX. DIP OF MCDONALD VEIN VARIES FROM 80 NE NEAR BLACK WONDER INTERSECTION TO NEAR VERTICAL FARTHER TO SE. BLACK WONDER VEIN TRENDS SUBPARELLEL TO TEWKSBURY VEIN AT N 10 TO 30 W AND MAY JOIN WITH IT ON IOWA LEVEL. PATTON (1917) DESCRIBES BLACK WONDER (OR GOLCONDA) VEIN AS CONTAINING UPPER OXIDIZED ORE ZONE 50 TO 300 FT IN DEPTH AND LOWER

Comment (Deposit): UNOXIDIZED SULFIDE ORE ZONE. IN OXIDIZED ZONE, FREE AU OCCURS IN LIMONITE OR LIMONITE-CLAP MIXTURE OR IN FE-STAINED QUARTZ GANGUE; NO CU. SULFIDE ZONE CONTAINS AURIFEROUS AND SLIGHTLY ARGENTIFEROUS PIR ITE, ENARGITE,AND SPORATIC GALENA AND SPHALERITE.

Comment (Workings): MINE DEVELOPED BY TWO TUNNELS: GOLCONDA 1 CROSSCUT TUNNEL (12070 FT PORTAL ELEV) DRIVEN S69W FOR 450 FT THROUGH BLACK WONDER VEIN. PRINCIPAL DRIFT DRIVEN SE AT 70 FT, WITH APPROX 340 FT DRIFT ON BLACK WONDER VEIN, 680 FT ON MCDONALD VEIN, 520 FT ON AZTEC VEIN. GOLCONDA 2 TUNNEL (11945 FT PORTAL ELEV) DRIVEN S69W FOR 510 FT THROUGH BLACK WONDER VEIN; APPROX 610 FT DRIFT ON BLACK WONDER VEIN, 200 FT ON AZTEC VEIN. TOTAL WORKINGS EXCLUSIVE OF RAISES/WINZES BETWEEN LEVELS INCLUDES APPROX 2130 FT ON GOLCONDA 1 AND 1520 FT ON GOLCONDA 2.

References

Reference (Deposit): LIPMAN, P.W., 1974, GEOLOGIC MAP OF THE PLATORO CALDERA AREA, SOUTHEASTERN SAN JUAN MOUNTAINS, SOUTHWESTERN COLORADO: USGS MAP I-828.

Reference (Deposit): PATTON, H.B., 1917, GEOLOGY AND ORE DEPOSITS OF THE PLATORO-SUMMITVILLE MINING DISTRICT, COLORADO: CGS BULL. 13.

Reference (Deposit): STEVEN, T.A., AND RATTE, J.C., 1960, GEOLOGY AND ORE DEPOSITS OF THE SUMMITVILLE DISTRICT, SAN JUAN MOUNTAINS, COLORADO: USGS PROF. PAPER 343

Colorado Mining Photos

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