Mohawk Mine

Past Producer in Keweenaw county in Michigan, United States with commodities Copper, Silver
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. Mineral occurrence model information
  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. Ownership information
  16. Production statistics
  17. Bibliographic references
  18. General comments
  19. Reporter information

Geologic information

Identification information

Deposit ID 10082872
MRDS ID W062236
Record type Site
Current site name Mohawk Mine

Geographic coordinates

Geographic coordinates: -88.35866, 47.305 (WGS84)

Site location context

Political divisions (FIPS codes)

Keweenaw(county)

Michigan(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Mohawk(quadrangle 1:24,000 scale)

Hancock(quadrangle 1:100,000 scale)

Hancock C(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Keweenaw Peninsula(hydrologic unit)

Southcentral Lake Superior(hydrologic accounting unit)

Southern Lake Superior(hydrologic subregion)

Great Lakes(hydrologic region)

Geographic areas

Country State County
United States Michigan Keweenaw

Public Land Survey System information

Meridian Township Range Section Fraction State
Michigan 057N 032W 33 Michigan

Comments on the location information

  • SHAFT NO. 3.

Commodities

Commodity Importance
Copper Primary
Silver Secondary

Comments on the commodity information

  • COPPER ARSENIDE MINERALS OCCUR WITH NATIVE COPPER IN FICOPPER ARSENIDE MINERALS OCCUR WITH NATIVE COPPER IN FISSURES THAT CROSS-CUT NATIVE COPPER DEPOSITS. NOTABLE FOR PRESENCE OF MOHAWKITE AND DOMEYKITE.

Materials information

Materials Type of material
Copper Ore
Feldspar Gangue
Epidote Gangue
Quartz Gangue
Calcite Gangue

Mineral occurrence model information

Model code 96
USGS model code Unassigned
Deposit model name Native Cu
Mark3 model number 99

Host and associated rocks

  • Host or associated Host
    Rock type Volcanic Rock (Aphanitic) > Mafic Volcanic Rock > Basalt
    Rock unit name Kearsarge Amygdaloid
    Rock description Kearsarge Amygdaloid
    Stratigraphic age (youngest) Stenian
    Chronological age 1095
  • Host or associated Host
    Rock type
    Rock unit name Portage Lake Volcanics
    Rock description Portage Lake Volcanics
    Stratigraphic age (youngest) Stenian
    Chronological age 1095

Nearby scientific data

(1) -88.35866, 47.305

Economic information

Ore body information

  • General form TABULAR

Controls for ore emplacement

  • Amygdaloidal basalt flow top

Comments on the geologic information

  • COPPER GRADE IN THE PRODUCTIVE PART OF THE KEARSARGE LODE APPEARS TO HAVE BEEN AS RICH AT OR VERY NEAR THE OUTCROP AS AT GREATER DEPTH, BUT THE REMAINDER OF THE LODE WAS RELATIVELY POOR AT THE SURFACE. AREAS OF LOW GRADE ORE NEAR THE SURFACE ARE COINCIDENT WITH AREAS OF RELATIVELY THIN OR CELLULAR, IMPERMEABLE LODE ROCKS.

Economic information about the deposit and operations

Development status Past Producer
Commodity type Metallic
Deposit size Medium
Significant No
Year of first production 1900
Year of last production 1931
Production years 1900-1901 PRODUCED MOHAWKITE; 1902-1925 AND LATER PRODUCED COPPER.

Mining district

District name Keweenaw Copper

Ownership information

  • Type Owner
    Owner Fulton Mining Co.
    First year 1898
  • Type Owner
    Owner Mohawk Mining Co. (organized in Nov 1898, took over part of the lands of Fulton Mining Co.)
    First year 1898

Production statistics

  • Year 1901
    Period 1900-1901
    Material ore mohawkite
    Ore mined 104.7mt
    Accuracy Accurate
  • Year 1925
    Period 1902-1925
    Accuracy Accurate
    Importance Item Commodity Group Amount recovered Grade Recovery percentage
    Major recovered Cu Copper Copper 117530mt

Comments on the workings information

  • AT THE SOUTH END OF MOHAWK, THERE WAS VERY GOOD GROUND IN THE UPPER LEVELS OF THE MINE. APPARENTLY ROCKS IN THE UPPER LEVELS OF THE MINE WERE AS GOOD AS THOSE DEEPER. KEARSARGE WAS ONE OF THE RICHEST LODES - ESPECIALLY NEAR HANGING WALL. LODE AVERAGES 6-13 FEET THICK IN AREA OF MINING ACTIVITY.

Comments on development

  • ECON.COM: WOLVERINE AND MICHIGAN CONSOLIDATED WITH MOHAWK ON AUG 15, 1923.

Reference information

Bibliographic references

  • Deposit

    BUTLER, B.S., AND BURBANK, W.S., 1929, THE COPPER DEPOSITS OF MICHIGAN: USGS PROF PAPER NO. 144, 238 PP.

  • Deposit

    WHITE, W.S., CORNWALL, H.R., AND SWANSON, R.W., 1953, BEDROCK GEOLOGY OF THE AHMEEK QUADRANGLE; USGS MAP GQ-27, SCALE 1:24000

  • Deposit

    DAVIDSON, E.S, ESPENSHADE, G.H., WHITE, W.S., AND WRIGHT, J.C., 1955, BEDROCK GEOLOGY OF THE MOHAWK QUADRANGLE, MICHIGAN: USGS MAP GQ-54, SCALE 1:24000.

  • Production

    BUTLER, B.S., AND BURBANK, W.S., 1929, P. 90.

General comments

Subject category Comment text
Deposit SEVERAL ARSENIDE FISSURES HAVE BEEN PROSPECTED IN THE NORTH END OF THE MOHAWK MINE. THE MAIN MINERALIZED AREA IS AT THE CROSSING OF THE KEARSARGE LODE AND EXTENDS FOR A SHORT DISTANCE INTO THE HANGING WALL OF THE KEARSARGE. A FISSURE OPENED SOUTH OF N0. 6 MOHAWK SHAFT CONTAINED SOME COPPER NEAR THE INTERSECTION WITH THE LODE. THE LODE IS ALSO REPORTED AS RICH NEAR THE FISSURE.

Reporter information

Type Date Name Affiliation Comment
Reporter 01-MAR-1996 Sutphin, D.M. (Cannon, W.F.) U.S. Geological Survey
Updater 01-MAR-1997 Sutphin, D.M. U.S. Geological Survey
Editor 01-MAY-1997 Mason Jr., G.T. U.S. Geological Survey

Beyond USGS

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