Northfield Prospect

Prospect in Lemhi county in Idaho, United States with commodities Copper, Cobalt, Nickel
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. Ore body information
  12. Controls for ore emplacement
  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. Reporter information

Geologic information

Identification information

Deposit ID 10067853
MRDS ID W000725
MAS/MILS ID 0160590418
Record type Site
Current site name Northfield Prospect
Alternate or previous names Stevenson, Merle 3 and 4

Geographic coordinates

Point of reference Ore Body
Geographic coordinates: -114.33211, 45.12657 (WGS84)
Elevation 2225
Location accuracy 100(meters)

Site location context

Political divisions (FIPS codes)

Lemhi(county)

Idaho(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Gant Mountain(quadrangle 1:24,000 scale)

Bighorn Crags(quadrangle 1:100,000 scale)

Elk City(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Middle Salmon-Panther(hydrologic unit)

Salmon(hydrologic accounting unit)

Lower Snake(hydrologic subregion)

Pacific Northwest(hydrologic region)

Federal lands

Salmon-Challis National Forest(National Forest)

National Forest FS(Type of land area)

FS(Federal land areas administered by FS)

Geographic areas

Country State County
United States Idaho Lemhi

Public Land Survey System information

Meridian Township Range Section Fraction State
Boise 021N 018E 22,26,27 Idaho

Commodities

Commodity Importance
Copper Primary
Cobalt Critical Primary
Nickel Critical Tertiary

Comments on the commodity information

  • Ore Occurs Disseminated And As Small Stringers Crossing The Shear Zones

Materials information

Materials Type of material
Chalcocite Ore
Chalcopyrite Ore
Cobaltite Ore
Copper Ore
Covellite Ore
Safflorite Ore
Apatite Gangue
Goethite Gangue
Pyrite Gangue
Pyrrhotite Gangue
Quartz Gangue

Alteration

  • (Local) limonitic
  • (Local) tourmalinization

Analytical data

Result AVG. 0.468 % CO, 1.245 % C

Host and associated rocks

  • Host or associated Host
    Rock type Metamorphic Rock > Metasedimentary Rock > Quartzite
    Rock unit name Banded siltite unit of Apple Creek Formation, Belt Supergroup
    Rock description Belt Supergroup-Schistose Quartz-Biotite
    Stratigraphic age (youngest) Mesoproterozoic
    Stratigraphic age (oldest) Mesoproterozoic
    Stratigraphic age (youngest) Mesoproterozoic
    Stratigraphic age (oldest) Mesoproterozoic

Nearby scientific data

Ore Body (1) -114.33211, 45.12657

Economic information

Ore body information

  • General form STRINGERS, IRREGULAR
    Strike N 12 DEG W
    Dip 65 DEG SW
    Plunge 55 DEG
    Plunge direction N
    Thickness 18.29M

Controls for ore emplacement

  • Gossan Zones

Comments on the geologic information

  • 5 N-NW Trending Gossan Zones (10-50 Ft. Wide) And Numerous N-Trending Zones (Up To 20 Ft. Wide). ; Geol.Desc: 5 North-Northwest Trending Gossan Zones(10-50 Ft. Wide)And Numerous North-Trending Zones(Up To 20 Ft. Wide)In Schistose Folded Quartz-Biotite Beds; Some Quartz Pods Present; Gossan Contains Goethite, Scorodite, Other Iron Arsenates, Copper Bloom, Some Cobaltite.
  • Original ore control entry:
    Gossan Zones

Economic information about the deposit and operations

Operation type Surface-Underground
Development status Prospect
Commodity type Metallic
Deposit size Small
Significant No
Discovery year 1951
Discoverer USGS

Mining district

District name Blackbird Mining District

Land status

Ownership category National Forest
Area name Salmon National Forest

Ownership information

  • Type Operator
    Owner Northfield Mines Inc.
    First year 1955
  • Type Owner
    Owner Floyd And Merle Stevenson

Comments on the reserve resource information

  • Because Of Incomplete Data No Specific Ore Reserves Have Been Calculated; However, If The Zones Are Continuous Reserves Up To 1300 Tons Of Ore Per Foot Of Depth, Having An Average Grade Of 0.453 Percent Cobalt And 1.176 Percent Copper, Are Indicated.

Workings at the site

  • Type of workings Surface/Underground
    Length 256.03M
    Overall depth 42.67M
    Overall length 6437.2M

Comments on the workings information

  • Pits, 4960 Ft. Diamond Drill Holes, Cat Road, Trenches

Comments on development

  • 44 Unpatented Claims And Fractions And 3 Patented Claims ; Econ.Com: Sheared Wall Rock Creates Difficult And Expensive Mining Conditions

Reference information

Bibliographic references

Reporter information

Type Date Name Affiliation Comment
Reporter 01-JUL-1972 Coury, Anny B. U.S. Geological Survey
Updater 01-SEP-1976 Duncan, Daniel G. (Miller, Pat) U.S. Geological Survey
Reporter 25-NOV-1983 Western Field Operations Center (WFOC) U.S. Bureau of Mines
Updater 05-FEB-2010 Causey, J. Douglas U.S. Geological Survey Combined data from MAS/MILS record number 0160590881.

Beyond USGS

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