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Gilt Edge Mine

Past Producer in Fergus county in Montana, United States with commodities Gold, Silver
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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. Mineral occurrence model information
  10. Host and associated rocks
  11. Nearby scientific data
  12. Geologic structures
  13. Ore body information
  14. Controls for ore emplacement
  15. Economic information about the deposit and operations
  16. Mining district
  17. Ownership information
  18. Reserves and resources
  19. Workings at the site
  20. Links to other databases
  21. Bibliographic references
  22. General comments
  23. Reporter information

Geologic information

Identification information

Deposit ID 10071313
MRDS ID W014640
Record type Site
Current site name Gilt Edge Mine
Alternate or previous names Gilt Edge Group, Virgin Gulch, Turtle Winds Shaft, Heath Mill

Geographic coordinates

Geographic coordinates: -109.22718, 47.14409 (WGS84)
Elevation 1524
Relative position ABOUT 20 MILES EAST OF LEWISTOWN, MONTANA

Site location context

Political divisions (FIPS codes)

Fergus(county)

Montana(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Judith Peak(quadrangle 1:24,000 scale)

Lewistown(quadrangle 1:100,000 scale)

Lewistown(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Box Elder(hydrologic unit)

Musselshell(hydrologic accounting unit)

Missouri-Musselshell(hydrologic subregion)

Missouri(hydrologic region)

Geographic areas

Country State County
United States Montana Fergus

Public Land Survey System information

Meridian Township Range Section Fraction State
Montana Principal 016N 020E 17,18,19 Montana

Commodities

Commodity Importance
Gold Primary
Silver Secondary

Comments on the commodity information

  • NO GOLD OR SILVER BEARING MINERALS HAVE BEEN RECOGNIZED, BUT IT HAS BEEN POSTULATED THAT THE GOLD IS IN THE FORM OF A FINELY DISSEMINATED TELLURIDE OR CONTAINED IN AURIFEROUS PYRITE.

Materials information

Materials Type of material
Pyrite Gangue

Alteration

  • (Local) Oxidation, Kaolinization

Mineral occurrence model information

Model code 84
USGS model code 22b
Deposit model name Alkaline Au-Te (Au-Ag-Te veins)
Mark3 model number 80

Host and associated rocks

  • Host or associated Associated
    Rock type Volcanic Rock (Aphanitic) > Felsic Volcanic Rock > Rhyolite
    Rock unit name Quartz Monzonite Porphyry Stock;Rhyolite Porphyry Dikes
    Rock description Quartz Monzonite Porphyry Stock;Rhyolite Porphyry Dikes
    Stratigraphic age (youngest) Mississippian
    Stratigraphic age (youngest) Pliocene
  • Host or associated Host
    Rock type Sedimentary Rock > Carbonate > Limestone
    Rock unit name Madison Limestone;Kibby Sandstone
    Rock description Madison Limestone;Kibby Sandstone

Nearby scientific data

(1) -109.22718, 47.14409
ListMap

Economic information

Geologic structures

Type of structure Regional
Structure description Large Laccolithic And Stock Intrusives Of Rhyolite And Quartz Monzonite
Type of structure Local
Structure description Doming And Faulting Produced By The Alpine Gulch Stock. Numerous Small Rhyolite Dikes.

Ore body information

  • General form POD/LENS
    Strike N
    Dip 30 DEG E
    Length 1000M
    Width 500M

Controls for ore emplacement

  • Mineralization Is Localized Beneath A 30 Foot Thick Rhyolite Porphyry Dike.

Comments on the geologic information

  • THE MINERALIZATION HAS OCCURRED BELOW THE RHYOLITE DIKE PRODUCING LARGE BODIES OF LOW GRADE ORE. REPLACEMENT OF LIMESTONE HAS PREDOMINATED, WITH LESSER AMOUNTS OF BRECCIA AND KIBBY SANDSTONE BEING REPLACED.

Economic information about the deposit and operations

Operation type Surface-Underground
Development status Past Producer
Commodity type Metallic
Deposit size Small
Significant Yes
Discovery year 1883
Discoverer L. R. Wilson
Year of first production 1883
Milling method Flotation

Mining district

District name Warm Springs - Gilt Edge District

Ownership information

  • Type Owner
    Owner Sunshine Mining Co.
    Home office Kellogg Idaho
  • Type Owner-Operator
    Owner Blue Range Mining Co. Ltd Partnership
    Interest 100
    Home office 305 W. Mercury St., Butte MT 59701
    First year 1988

Reserves and resources

  • Type In-situ
    Estimate year 1990
    Measured 136080mt ore
    Commodity Subtype Grade units Group Importance Year
    Gold 5.3 g/mt Gold Major 1990

Comments on the reserve resource information

  • 1. LARGE AMOUNTS OF BLACK OR UNOXIDIZED ORE ARE REPORTEDLY PRESENT AT DEPTH. 2. THIS IS REPORTED AS OXIDIZED ORE LEFT AS PILLARS IN THE OLD STOPES.

Workings at the site

  • Type of workings Surface/Underground
    Area 50HA
    Length 3000M
    Overall depth 100M
    Overall length 914.4M
    Overall width 500M

Comments on the workings information

  • MINE IS DEVELOPED BY A 1650-FOOT MAIN HAULAGE TUNNEL, THE 1700-FOOT STANDBY CROSSCUT, A 185-FOOT WINZE BELOW THE HAULAGE LEVEL, AND NUMEROUS SMALL ADITS, INCLINES AND SHAFTS. SEVERAL THOUSAND FEET OF CROSSCUTS AND RAISES PROSPECT THE ORE ZONE. SEVERAL THOUSAND FEET OF STOPED GROUND, UP TO 90 FEET HIGH AND 300 FEET WIDE, AND SEVERAL OPEN PITS EXTEND ALONG THE STRIKE OF THE ORE BODIES.

Reference information

Bibliographic references

  • Deposit

    FORREST, R. A., 1971, GEOLOGY AND MINERAL DEPOSITS OF THE WARM SPRINGS - GILT EDGE DISTRICT, FERGUS COUNTY, MONTANA M. S. THESIS MONTANA TECH, BUTTE MONTANA

  • Deposit

    ROBERTSON, A. F., 1950, MINES AND MINERAL DEPOSITS, FERGUS COUNTY, MONT.: U. S. BUREAU OF MINES INF. CIRC. 7544

  • Production

    FORREST, 1971; USBM INF. CIRC. 7544

General comments

Subject category Comment text
Deposit THE OXIDIZED ORE IS EASILY TREATED BY CYANIDATION, BUT UNOXIDIZED ORE MUST BE TREATED IN THE ROASTING CIRCUIT TO RECOVER THE GOLD WITH THE CYANIDE PROCESS.
Deposit Merged data from Deposit ID 10148604 (Giltedge)

Reporter information

Type Date Name Affiliation Comment
Reporter 01-DEC-76 Swanson, Leroy J.; Krohn, D. H. U.S. Geological Survey

Beyond USGS

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

External references

Maps centered on this site