Bonnie Girl Mine

The Bonnie Girl Mine is a gold and silver mine located in La Plata county, Colorado at an elevation of 10,699 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

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Site Name

Primary: Bonnie Girl Mine
Secondary: Baker Contact

Commodity

Primary: Gold
Primary: Silver
Tertiary: Copper

Location

State: Colorado
County: La Plata
District: California (La Plata) 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: Past Producer
Deposit Type: Vein
Operation Type: Unknown
Year First Production: 1895
Year Last Production: 1919
Discovery Year: 1895
Discovery Method: Ore-Mineral In Place
Years of Production:
Organization:
Significant: N
Deposit Size: S

Physiography

General Physiographic Area: Intermontane Plateaus
Physiographic Province: Colorado Plateaus
Physiographic Section: Navajo Section

Mineral Deposit Model

Model Name: Polymetallic veins

Orebody

Not available

Structure

Type: R
Description: San Juan Uplift, Four Corners Platform

Type: L
Description: La Plata Dome

Alterations

Alteration Type: L
Alteration Text: Oxidation Of Pyrite To Limonite

Rocks

Name: Diorite
Role: Associated
Age Type: Associated Rock
Age Young: Paleocene

Name: Diorite
Role: Associated
Age Type: Associated Rock Unit
Age Young: Paleocene

Name: Diorite
Role: Associated
Age Type: Host Rock Unit
Age Young: Late Permian

Name: Diorite
Role: Associated
Age Type: Host Rock
Age Young: Late Permian

Analytical Data

Not available

Materials

Ore: Chalcopyrite
Gangue: Garnet
Gangue: Magnetite

Comments

Comment (Location): (LAND STATUS AND ADMINISTRATIVE AREA LOCATIONS CALCULATED USING GIS OVERLAY ANALYSIS FOR SAN JUAN N. F.). NE OF TIRBIRCIO CREEK ON WEST SLOPE OF BAKER PEAK, 1.35 MILES ENE OF LA PLATA TOWNSITE (UNSURVEYED SECTION). ; INFO FROM LAND.ST :1974

Comment (Deposit): COUNTRY ROCK CONSISTS OF METAMORPHOSED CUTLER FM RED BEDS INTRUDED BY DIORITE-MONZONITE PORPHYRY SILLS AND DIKES AND CUT BY ENE-WSW-TRENDING VEIN. NO STRONG VEINS WERE SEEN IN MINE WORKINGS BUT RATHER MANY ZONES AND LENSES OF BRECCIATED AND ALTERED ROCK BEARING PYRITE AND QUARTZ. GOLD PRODUCED BELIEVED TO HAVE BEEN FROM OXIDIZED ZONE NEAR SURFACE.

Comment (Workings): MAIN WORKING IS SMALL HILLSIDE OPEN CUT; SEVERAL EXPLORATORY ADITS TOTALING 700 FT; 225-FT ADIT DRIVEN N 80 E SITUATED JUST EAST OF OPEN CUT; LOWER TUNNEL DRIVEN N 32 E FOR 125 FT WITH GENERALLY EASTWARD BRANCH 140 FT DRIVEN AT 45 FT FROM PORTAL: REMNANTS OF AERIAL TRAM THAT CONNECTED MINE TO GOLD KING MILL.

Comment (Production): PARTIAL PRODUCTION RECORD. PRODUCTION PRIOR TO 1902 UNKNOWN BUT CONSIDERED SMALL. NO PRODUCTION FOR OTHER YEARS EXCEPT THOSE SHOWN.

Comment (Development): DEPOSIT DISCOVERED 1895 OR EARLIER AND PERHAPS PRODUCED SMALL AMOUNT OF ORE TO 1902. RECORDED INTERMITTENT PRODUCTION IN 1906, 1908, AND 1919. ABOUT 1904, 50-STAMP MILL BUILT AT MOUTH OF TIRBIRCIO CREEK AND WAS CONNECTED TO MINE VIA AERIAL TRAM. MILL OPERATED ONLY A FEW YEARS, BUT RUMOR SAYS IT PRODUCED LARGE QUANTITY OF AMALGAM, BUT US MINT FOUND IT TO CONTAIN CU RATHER THAN AU. MILL LATER REMODELED AS GOLD KING MILL.

References

Reference (Deposit): ECKEL, E.B., AND OTHERS, 1949, GEOLOGY AND ORE DEPOSITS OF THE LA PLATA DISTRICT, COLORADO: USGS PROF. PAPER 219, P. 67-68, 96-97

Reference (Production): ECKEL AND OTHERS, 1949 (AS COMPILED FROM USGS AND USBM RECORDS)

Colorado Mining Photos

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