The Mary L. Group is a uranium mine located in Fremont county, Colorado at an elevation of 8,199 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
Elevation: 8,199 Feet (2,499 Meters)
Commodity: Uranium
Lat, Long: 38.58278, -105.52417
Map: View on Google Maps
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Mary L. Group MRDS details
Site Name
Primary: Mary L. Group
Secondary: Mary L. 1-6 Claims
Commodity
Primary: Uranium
Location
State: Colorado
County: Fremont
District: Tallahassee Creek
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: Unknown
Ownership
Owner Name: John T. Fontecchio, E.J. Smaller
Years: 1980 -
Production
Year: 1962
Time Period: 1955-1962
Mined: 2179.000 mt
Material type: Ore
Description: Cp_Grade: ^0.24% U308
Deposit
Record Type: Site
Operation Category: Past Producer
Operation Type: Surface-Underground
Year First Production: 1955
Discovery Year: 1954
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: Sandstone U
Orebody
Form: TABULAR, PODS, LENTICULAR BODIES
Structure
Type: R
Description: Thirty Nine Mile Volcanic Field, Currant Creek Basin
Type: L
Description: Echo Park Graben, Paleovalleys; North-South Trending Reverse Fault Places Precambrian Granite And Schist Against Tertiary Sandstones, Limiting Ore Body On East. Fault Strikes N 35-45 W, Dips 40 Ne; Numerous Small Faults And Fractures Increased Permeability Of Sediments
Alterations
Alteration Type: L
Alteration Text: Oxidation; Alteration Of Feldspar To Clay
Rocks
Name: Rhyolite
Role: Associated
Age Type: Associated Rock Unit
Age Young: Oligocene
Name: Rhyolite
Role: Associated
Age Type: Host Rock Unit
Age Young: Eocene
Name: Rhyolite
Role: Associated
Age Type: Host Rock
Age Young: Eocene
Name: Rhyolite
Role: Associated
Age Type: Associated Rock
Age Young: Oligocene
Analytical Data
Analytical Data: DISEQUILIBRIUM RATIOS ON ORE SAMPLES GENERALLY FAVOR CHEMICAL U308
Materials
Ore: Uraninite
Ore: Torbernite
Ore: Coffinite
Gangue: Hematite
Gangue: Pyrite
Gangue: Calcite
Gangue: Limonite
Gangue: Gypsum
Comments
Comment (Development): DISCOVERED BY GROUND RADIOMETRIC ANOMALIES-NO OUTCROP PRESENT; DRILLING OUTLINED ORE BODY
Comment (Geology): DEPOSITS LOCALIZED AND PRESERVED BY SLUGGISH GROUNDWATER MOVEMENT IN AREA. THOSE CONDITIONS STILL PRESENT AS EVIDENCED BY ARTESIAN PRESSURE IN WELLS AND SPRINGS ISSUING FROM ECHO PARK FORMATION AND BY A PRESENT URANIUM CONTENT OF GROUNDWATER IN AREA AS HIGH AS 900 PPB.
Comment (Location): PROPERTY ADJOINS SMALLER AND JOAN MINES ; INFO FROM LAND.ST :1976
Comment (Location): Location based on USAEC 1955 preliminary recon. report.
Comment (Workings): OPEN PIT, UNDERGROUND WORKINGS OFF OF PIT WALLS
Comment (Deposit): THE DEPOSIT IS RELATIVELY FLAT-LYING WITH LOCAL THICKENING AND THINNING. THE UNDERLYING GRANITE IS MINERALIZED BUT DOES NOT CONTAIN KNOWN ORE. PART OF THE ORE BODY DESCRIBED ABOVE MAY HAVE BEEN MINED AS THE SMALLER AND JOAN 2 MINES, WHICH ADJOIN THIS PROPERTY
References
Reference (Deposit): EPIS, R.C., WOBUS, R.A. AND SCOTT, G.R., 1979, GEOLOGIC MAP OF THE BLACK MOUNTAIN QUADRANGLE, FREMONT AND PARK COUNTIES, COLORADO: USGS MAP I-1195, 1:62,500.
Reference (Deposit): DICKINSON, K.A., 1981, GEOLOGIC CONTROLS OF URANIUM MINERALIZATION IN THE TALLAHASSEE CREEK URANIUM DISTRICT, FREMONT COUNTY, COLORADO: THE MOUNTAIN GEOLOGIST, V. 18, NO. 4, P. 88-94.
Reference (Deposit): SIMON, M.R., 1956, URANIUM DEPOSITS OF CENTRAL AND SOUTH-CENTRAL COLORADO, IN GUIDEBOOK TO THE GEOLOGY OF THE RATON BASIN, COLORADO: ROCKY MOUNTAIN ASSOCIATION OF GEOLOGISTS GUIDEBOOK, P. 84.
Reference (Deposit): BABCOCK, J.A., 1980, TALLAHASSEE CREEK URANIUM DEPOSITS: DENVER REGIONAL EXPLORATION GEOLOGISTS SOCIETY GUIDEBOOK, P. 15-31.
Reference (Deposit): MACPHERSON, B.A., 1959, GEOLOGY AND URANIUM DEPOSITS OF THE TALLAHASSEE CREEK DISTRICT, FREMONT COUNTY, COLORADO: US ATOMIC ENERGY COMMISSION RME-1083, 39 P.
Reference (Production): NELSON-MOORE AND OTHERS, 1978
Reference (Deposit): NELSON-MOORE, J.L., COLLINS, D.B. AND HORNBAKER, A.L., 1978, RADIOACTIVE MINERAL OCCURRENCES OF COLORADO AND BIBLIOGRAPHY: Colorado Geological Survey Bulletin 40,P. 150.
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