Maybell Mines

Producer in Moffat county in Colorado, United States with commodities Uranium, Molybdenum
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Public Land Survey System information
  6. Commodities
  7. Materials information
  8. Alteration
  9. Host and associated rocks
  10. Nearby scientific data
  11. Geologic structures
  12. Ore body information
  13. Economic information about the deposit and operations
  14. Mining district
  15. Land status
  16. Ownership information
  17. Workings at the site
  18. Links to other databases
  19. Bibliographic references
  20. General comments
  21. Reporter information

Geologic information

Identification information

Deposit ID 10107975
MRDS ID D008020
Record type Site
Current site name Maybell Mines
Alternate or previous names Marge Mine, Gertrude Pits, Trace Elements Pits
Related records 10287941

Geographic coordinates

Geographic coordinates: -107.99511, 40.54719 (WGS84)
Elevation 1908
Relative position 5.6 MILES N 58 E FROM MAYBELL

Site location context

Political divisions (FIPS codes)

Moffat(county)

Colorado(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Lay(quadrangle 1:24,000 scale)

Craig(quadrangle 1:100,000 scale)

Craig(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Lower Yampa(hydrologic unit)

White-Yampa(hydrologic accounting unit)

White-Yampa(hydrologic subregion)

Upper Colorado(hydrologic region)

Federal lands

Bureau of Land Management(Bureau of Land Management CO)

Bureau of Land Management CO BLM(Type of land area)

BLM(Federal land areas administered by BLM)

Geographic areas

Country State County
United States Colorado Moffat

Public Land Survey System information

Meridian Township Range Section Fraction State
6th Principal 007N;007N 094W;095W 07,08,17,18,19;13,24 Colorado

Comments on the location information

  • 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)

Commodities

Commodity Importance
Uranium Primary
Molybdenum Secondary

Comments on the commodity information

  • URANINITE AND COFFINITE IN UNOXIDIZED ZONE; URANOPHANE AND META-AUTUNITE IN OXIDIZED ZONE

Materials information

Materials Type of material
Ilsemannite Ore
Jordisite Ore
Uranophane Ore
Calcite Gangue
Clay Gangue
Gypsum Gangue
Jarosite Gangue
Limonite Gangue
Pyrite Gangue
Quartz Gangue

Alteration

  • (Local) Oxidation Of Fe And U Minerals

Analytical data

Result 1971 ORE GRADE REPORTED FROM MARGE MINE WAS 0.16% U3O8
Result 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
Result 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.

Host and associated rocks

  • Host or associated Host
    Rock type Sedimentary Rock > Clastic Sedimentary Rock > Sandstone
    Rock unit name Browns Park Formation
    Rock description Browns Park Formation
    Stratigraphic age (youngest) Pliocene

Nearby scientific data

(1) -107.99511, 40.54719

Economic information

Geologic structures

Type of structure Regional
Structure description Washakie Basin, Axial Basin
Type of structure Local
Structure description Lay Syncline, Maybell Monocline, Normal Fault (Unnamed)

Ore body information

  • General form LENTICULAR
    Strike N 70 E
    Dip 30 NW
    Thickness 9.14M
    Length 304.8M
    Depth to top 1.83M
    Depth to bottom 60.96M

Economic information about the deposit and operations

Development status Producer
Commodity type Metallic
Significant No
Discovery year 1954
Year of first production 1955

Mining district

District name Maybell District

Land status

Ownership category BLM Administrative Area

Ownership information

  • Type Operator
    Owner Donald G. Steele Construction Co.
    First year 1980
  • Type Owner
    Owner Union Carbide Corp.
    First year 1980

Comments on the production information

  • 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.

Workings at the site

  • Type of workings Surface/Underground
    Area 284.9HA

Comments on the workings information

  • 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.

Comments on 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.

Reference information

Bibliographic references

General comments

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

Reporter information

Type Date Name Affiliation Comment
Reporter 01-NOV-1981 Schwochow, Stephen D. (King, Robert U.) Colorado Geological Survey

Beyond USGS

Supplemental information added by qvyshift.com. Not part of the original USGS MRDS record.

Authoritative Colorado resources

These are landing pages for further research — the state agencies don't currently expose per-mine deep links.