Mason Mine

Producer in Larimer county in Colorado, United States with commodities Gold, Silver, Tungsten
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. Controls for ore emplacement
  14. Economic information about the deposit and operations
  15. Mining district
  16. Land status
  17. Links to other databases
  18. Bibliographic references
  19. General comments
  20. Reporter information

Geologic information

Identification information

Deposit ID 10013973
MRDS ID D010552
Record type Site
Current site name Mason Mine
Alternate or previous names Mason Ranch Mine
Related records 10239742

Geographic coordinates

Geographic coordinates: -105.21115, 40.50081 (WGS84)
Elevation 1743
Relative position 9.1 MILES S51W FROM FORT COLLINS

Site location context

Political divisions (FIPS codes)

Larimer(county)

Colorado(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Horsetooth Reservoir(quadrangle 1:24,000 scale)

Fort Collins(quadrangle 1:100,000 scale)

Greeley(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Big Thompson(hydrologic unit)

South Platte(hydrologic accounting unit)

South Platte(hydrologic subregion)

Missouri(hydrologic region)

Geographic areas

Country State County
United States Colorado Larimer

Public Land Survey System information

Meridian Township Range Section Fraction State
6th Principal 006N 070W 10 NE OF SE Colorado

Comments on the location information

  • ON HILLSIDE ABOVE BUCKHORN CREEK 0.9 MILE NNW FROM MASONVILLE. ; INFO FROM LAND.ST :1980

Commodities

Commodity Importance
Gold Primary
Silver Primary
Tungsten Critical Primary

Materials information

Materials Type of material
Pyrite Ore
Scheelite Ore
Epidote Gangue
Hematite Gangue
Montmorillonite Gangue
Quartz Gangue

Alteration

  • (Local) Hydrothermal Montmorillonite In Fractures

Analytical data

Result VEIN ASSAYED 0.02 TO 0.04 OZ/TON AU, 0.4 TO 0.6 OZ/TON AG
Result HIGHER GRADE AU ORE IN SHAFT ASSAYED 2 OZ/TON AU.

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Granitoid > Tonalite
    Rock unit name Tonalite
    Rock description Tonalite
    Stratigraphic age (youngest) Neoproterozoic
    Stratigraphic age (youngest) Neoproterozoic
    Stratigraphic age (youngest) Neoproterozoic
  • Host or associated Host
    Rock type Plutonic Rock > Granitoid > Tonalite
    Rock unit name Tonalite;Metasedimentary Rocks--Mica Schist
    Rock description Tonalite;Metasedimentary Rocks--Mica Schist

Nearby scientific data

(1) -105.21115, 40.50081

Economic information

Geologic structures

Type of structure Regional
Structure description Front Range Uplift, Cheyenne Basin
Type of structure Local
Structure description Big Thompson Anticline, Milner Mountain Fault, Fletcher Hill (Buck Horn) Fault, Masonville Anticline, Buckhorn Syncline, Masonville Stock , Redstone Fault

Ore body information

  • Thickness 1.22M

Controls for ore emplacement

  • Primary Joints And Fractures In Stock

Economic information about the deposit and operations

Development status Producer
Commodity type Metallic
Deposit size Small
Significant No

Mining district

District name Masonville District

Land status

Ownership category Federal

Comments on the workings information

  • MINE DEVELOPED BY 122-FT INCLINED SHAFT, 960-FT ADIT WITH 200 FT OF DRIFTS.

Comments on development

  • SHAFT ORIGINALLY PENETRATED SCHEELITE WHICH WAS THROWN ON DUMP. S HAFT FLOODED BEFORE HIGHER GRADE AU ORE COULD BE WORKED. CROSSCUT TUNN EL DRIVEN FROM BELOW TO WORK DEPOSIT.

Reference information

Bibliographic references

  • Deposit

    WOLFE, J.A., 1953, GEOLOGY OF THE MASONVILLE MINING DISTRICT, LARIM ER COUNTY, COLORADO: COLORADO SCHOOL OF MINES M.SC. THESIS T-789.

  • Deposit

    BRADDOCK, W.A., AND OTHERS, 1970, GEOLOGIC MAP OF THE MASONVILLE QU ADRANGLE, LARIMER COUNTY, COLORADO: USGS MAP GQ-832.

  • Deposit

    COBB, H.S., 1960, TUNGSTEN MINES OF COLORADO: COLORADO METAL MINING FUND BD., P. 49.

  • Deposit

    BELSER, CARL, 1956, TUNGSTEN POTENTIAL IN CHAFFEE, FREMONT, GUNNISO N, LAKE, LARIMER, PARK, AND SUMMIT COUNTIES, COLORADO: USBM IC-7748, P . 18.

General comments

Subject category Comment text
Deposit NW-TRENDING FRACTURES CONTAINED EITHER MONTMORILLONITE OR MONTMOR ILLONITE-EPIDOTE-HEMATITE-QUARTZ. MOST NE-TRENDING FRACTURES CONTAINED MONTMORILLOMITE-OR MONTMORILLONITE-EPIDOTE. PYRITE CONCENTRATIONS FOUN D AT SLIGHT CHANGES IN STRIKE ALONG N30E-TRENDING FRACTURE

Reporter information

Type Date Name Affiliation Comment
Reporter 01-APR-1983 Schwochow, Stephen D. 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.