Colorado-American Mine

The Colorado-American Mine is a fluorine-fluorite mine located in Chaffee county, Colorado at an elevation of 7,720 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: Colorado-American Mine
Secondary: American Shaft
Secondary: Trefone Adit or Tunnel
Secondary: Mill Adit
Secondary: Kramer Adit
Secondary: American Fluorspar Co. Mine
Secondary: Colorado Fluorspar Co. Mine
Secondary: Browns Canyon Deposit
Secondary: Arkansas Claim
Secondary: Bapp (Bopp) Mine
Secondary: Browns Canyon or Dostal Mine

Commodity

Primary: Fluorine-Fluorite
Tertiary: Manganese

Location

State: Colorado
County: Chaffee
District: Browns Canyon 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

Owner Name: Allied Chemical Corp., General Chemical Division
Years: 1969 -

Production

Year: 1948
Time Period: 1930-1948
Mined: 115151.400 mt
Material type: FLUORSPAR CONCENTRATES
Description: Cp_Grade: ^50% Caf2

Deposit

Record Type: Site
Operation Category: Past Producer
Operation Type: Unknown
Year First Production: 1927
Year Last Production: 1949
Discovery Year: 1923
Discovery Method: Ore-Mineral In Place
Years of Production:
Organization:
Significant: N
Deposit Size: M

Physiography

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

Mineral Deposit Model

Model Name: Fluorspar deposits (fluorite veins)

Orebody

Form: TABULAR, LENTICULAR, POD-LIKE

Structure

Type: R
Description: Southern Mosquito Range, Arkansas Valley Graben

Type: L
Description: Folds, Faults; N-Trending Fault Bounding Arkansas Valley; At 100-Ft Level Of Mine Workings Expose Fault With Welded Tuff On One Side, Quartz Monzonite On Other Side

Alterations

Alteration Type: L
Alteration Text: Silicification, Fluoritization

Rocks

Name: Gneiss
Role: Associated
Age Type: Associated Rock Unit
Age Young: Neoproterozoic

Name: Gneiss
Role: Associated
Age Type: Host Rock Unit
Age Young: Neoproterozoic

Analytical Data

Analytical Data: EAST VEIN AVERAGES 50% CAF2, WITH LARGE POCKETS AVERAGING 75% CAF2

Materials

Ore: Fluorite
Gangue: Psilomelane
Gangue: Pyrite
Gangue: Quartz
Gangue: Hematite
Gangue: Kaolinite
Gangue: Montmorillonite
Gangue: Barite
Gangue: Calcite
Gangue: Manganite
Gangue: Goethite
Gangue: Pyrolusite
Gangue: Opal

Comments

Comment (Development): Originally two mines, the American Fluorspar Corp. mine on the NW and the Colorado Fluorspar Co. mine to the SE, these properties were later combined and operated as one mine.

Comment (Location): SE OF HECLA JUNCTION, EAST OF US HWY 285, WEST OF ARKANSAS RIVER; N/2 SEC. 34, T 51 N, R 8 E. INFO FROM LAND.ST :(1976)

Comment (Production): ABOUT 90% OF FLUORSPAR CONCENTRATES SHIPPED FROM DISTRICT CAME FROM THIS MINE. ALMOST 60% OF THE CONCENTRATES WERE METALLURGICAL-GRADE (85% CAF2), 40% WERE CERAMIC-GRADE (92-97% CAF2), AND 2% WERE ACID-GRADE (98% CAF2).

Comment (Workings): OPEN PIT, SHAFTS, DRIFTS, ADITS, CROSSCUTS, STOPES;

Comment (Deposit): SOUTHERN PART OF MINE HAS BEEN RICHEST PRODUCER;, 3 MAIN VEINS: EAST VEIN, WEST VEIN, AND THE BRANCH OR COLLINS VEIN. EAST AND WEST VEINS STRIKE N 40 W, DIP 65-85 SW; BRANCH VEIN STRIKES WEST, DIPS 45 S. EAST AND WEST VEINS ARE 120-200 FT APART AND WEST AND BRANCH VEINS INTERSECT NEAR SOUTH END OF MINE. EAST VEIN IS ALONG FAULT IN PRECAMBRIAN ROCKS. WEST AND BRANCH VEINS FOLLOW FAULT ZONES BETWEEN PRECAMBRIAN AND TERTIARY FAULTS. EAST VEIN IS PRINCIPAL ORE BODY. IN THE OPEN PIT THE BRANCH VEIN REACHES WIDTHS OF 50 FT OR MORE.

References

Reference (Development): LINTNER, R. E. COLORADO FLUORSPAR MINES, INCORPORATED, SALIDA, COLORADO. DECO TREFOIL MAGAZINE, ENGINEERING NOTE-BOOK BULL. M4-B47, NOVEMBER-DECEMBER 1947, 8 PP.

Reference (Production): VAN ALSTINE, R. E. (1969)

Reference (Deposit): COLO BOM AN RPT 1941, 1943

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

Reference (Deposit): VANDERWILT, 1947, COLO. MINERAL RES. BOARD

Reference (Deposit): VAN ALSTINE, R. E. AND COX, D. C., 1969, FLUORSPAR MINES AND PROSPECTS, IN, GEOLOGY AND MINERAL DEPOSITS OF THE PONCHA SPRINGS NE QUADRANGLE, CHAFFEE COUNTY, COLORADO: USGS PROFESSIONAL PAPER 626, P. 38-43

Reference (Deposit): BRADY, B. T., 1975, MAP SHOWING FLOORSPAR DEPOSITS IN COLORADO: USGS MAP MR-70, 1:500,000, TEXT

Reference (Deposit): MINE MAP REPO # 404957

Reference (Deposit): MICROFILM DOCUMENT 2565: MINERAL DEPOSITS BRANCH IN LIBRARY

Reference (Deposit): CONSV. DIV. COMP. DATE, 1,64

Reference (Deposit): USGS TOPO MAPS ARKANSAS RIVER SURVEY, 1955, 1: 24,000;

Reference (Deposit): ARGALL, 1949, COLO.SCH. MINES QUART., V. 44, NO. 2

Reference (Deposit): VAN ALSTINE, R. E., 1969, GEOLOGY AND MINERAL DEPOSITS OF THE PONCHA SPRINGS NE QUADRANGLE, CHAFFEE COUNTY, COLORADO: USGS PROFESSIONAL PAPER 626, 52 P.

Colorado Mining Photos

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