Maybell Mines

The Maybell Mines is a uranium mine located in Moffat county, Colorado at an elevation of 6,260 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: Maybell Mines
Secondary: Marge Mine
Secondary: Gertrude Pits
Secondary: Trace Elements Pits

Commodity

Primary: Uranium
Secondary: Molybdenum

Location

State: Colorado
County: Moffat
District: Maybell District

Land Status

Land ownership: BLM Administrative Area
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: Union Carbide Corp.
Years: 1980 -

Owner Name: Donald G. Steele Construction Co.
Years: 1980 -

Production

Not available

Deposit

Record Type: Site
Operation Category: Producer
Operation Type: Unknown
Year First Production: 1955
Discovery Year: 1954
Discovery Method: Other
Years of Production:
Organization:
Significant: N

Physiography

General Physiographic Area: Rocky Mountain System
Physiographic Province: Wyoming Basin

Mineral Deposit Model

Not available

Orebody

Form: LENTICULAR

Structure

Type: R
Description: Washakie Basin, Axial Basin

Type: L
Description: Lay Syncline, Maybell Monocline, Normal Fault (Unnamed)

Alterations

Alteration Type: L
Alteration Text: Oxidation Of Fe And U Minerals

Rocks

Name: Sandstone
Role: Host
Age Type: Host Rock Unit
Age Young: Pliocene

Analytical Data

Analytical Data: BACKGROUND RADIATION 0.02 MR/HR WITH RANGE OF 0.05 TO 4.5 MR/HR. CHANNEL SAMPLES FROM GERTRUDE ASSAYED 0.212 TO 0.236 % EQUIV. U3O8 AND 0.212 TO 0.543 % U3O8.
Analytical Data: BACKGROUND RADIATION 0.02 MR/HR WITH RANGE OF 0.05 TO 2.0 MR/HR. 1971 ORE GRADE REPORTED FROM GERTRUDE PITS WAS 0.12% U3O8
Analytical Data: 1971 ORE GRADE REPORTED FROM MARGE MINE WAS 0.16% U3O8

Materials

Ore: Uranophane
Ore: Jordisite
Ore: Ilsemannite
Gangue: Quartz
Gangue: Pyrite
Gangue: Gypsum
Gangue: Calcite
Gangue: Limonite
Gangue: Clay
Gangue: Jarosite

Comments

Comment (Location): ON UNNAMED TRIBUTARIES OF LAY CR. AND YAMPA RIVER. LAT-LONG GIVEN IS C NW/4 SEC. 19 IN MARGE PIT. ; INFO FROM LAND.ST :(1974)

Comment (Commodity): URANINITE AND COFFINITE IN UNOXIDIZED ZONE; URANOPHANE AND META-AUTUNITE IN OXIDIZED ZONE

Comment (Deposit): ORE OCCURS AS FLAT TO IRREGULAR LENSES IN VERY FINE-TO MEDIUM-GRAINED, CROSS-BEDDED, TUFFACEOUS SANDSTONE. NORMAL FAULT CUTTING MARGE DEPOSIT TRENDS N 3 W, DOWNDROPPED NE, AND HAS TWO SMALLER BRANCH FAULTS TRENDING N 60 W (WRIGHT AND EVERHART, 1960). GERTRUDE DEPOSIT CUT BY THREE INFERRED NORMAL FAULTS IN S-SHAPE FASHION TRENDING N 40 TO 90 W. OXIDIZED URANIUM MINERALS OCCUR AS YELLOW STAINS AND SMEARS ASSOCIATED WITH LIMONITE STAINS. UNOXIDIZED MINERALS ARE NOT VISIBLE MEGASCOPICALLY BUT OCCUR IN BLUISH TO GRAYISH SANDSTONE. COLOR CHANGE MARKING THIS CONTACT RANGES IN DEPTH FROM 10 TO 440 FT.

Comment (Workings): MINES DEVELOPED BY SERIES OF OPEN PITS 500 TO 1000 FT LONG, 175 TO 500 FT WIDE, AND 35 TO 175 FT DEEP. A FEW UNDERGROUND TUNNELS FROM 300 TO 750 FT LONG WERE DRIVEN INTO PIT WALLS LATER, AND SMALL AMOUNTS OF ORE APPARENTLY STOPED. MOST RECENT ACTIVITY EXTRACTED ORE FROM DRAINED MARGE PIT, USED PROCESS WATER FROM GERTRUDE PITS. ORE MILLED AT UNION CARBIDE PLANT IN MAYBELL.

Comment (Deposit): D000452 HAS BEEN MERGED WITH THIS RECORD AND DELETED. ; INFO.SRC : 1 PUB LIT; 2 UNPUB REPT

Comment (Production): CDM RECORDS DO NOT SHOW CONTINUOUS PRODUCTION HISTORY SINCE 1955. RECORDS THRU 1962 ARE UNDER NAME OF TRACE ELEMENTS CORP. (UNIT OF UNION CARBIDE CORP.). 1955 TONNAGE FROM GERTRUDE NO. 6; 1956 FROM MARGE NO. 1 AND GERTRUDE NOS. 1 TO 18, RESPECTIVELY; 1957 FROM MARGE NOS. 1 AND 2; 1960-62 FROM MAYBELL MINE AND TRACE ELEMENTS PITS. CONCENTRATES ARE U3O8.

Comment (Development): MAYBELL DEPOSITS DISCOVERED IN 1954 BY AIRBORNE DETECTION EQUIPMENT . APPARENTLY NO PRODUCTION SINCE 1962, ALTHO MAYBELL PLANT CONTINUED TO PROCESS CONCENTRATES FROM ORE. BY 1982 PLANT CONSISTED OF 55-ACRE HEAP LEACHING OPERATION ON LOW-GRADE ORE.

References

Reference (Deposit): NELSON-MOORE, J.L., COLLINS, D.B., AND HORNBAKER, A.L., 1978, RADIOACTIVE MINERAL OCCURRENCES OF COLORADO AND BIBLIOGRAPHY; COLORADO GEOLOGICAL SURVEY BULL. 40, P. 268, 271.

Reference (Deposit): MCKAY, E.J., AND BERGIN, M.J., 1974, GEOLOGIC MAP OF THE MAYBELL QUADRANGLE, MOFFAT COUNTY, COLORADO: USGS GQ-1145.

Reference (Deposit): WRIGHT, R.J., AND EVERHART, D.L., 1960, URANIUM, IN DEL RIO, S.M., MINERAL RESOURCES OF COLORADO-FIRST SEQUEL: COLO. STATE MINERAL RESOURCES BD., P. 343-347.

Reference (Deposit): KING, R.U., (UNPUBLISHED DATA)

Reference (Production): COLO. DIV. MINES ANN. OPERATOR REPTS.

Colorado Mining Photos

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