Unnamed (along Kuskokwim River)

Occurrence in Alaska, United States with commodities Silver, Copper, Lead, Nickel
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Commodities
  6. Materials information
  7. Alteration
  8. Mineral occurrence model information
  9. Nearby scientific data
  10. Economic information about the deposit and operations
  11. Mining district
  12. Links to other databases
  13. Bibliographic references
  14. General comments
  15. Reporter information

Geologic information

Identification information

Deposit ID 10307826
Record type Site
Current site name Unnamed (along Kuskokwim River)

Geographic coordinates

Geographic coordinates: -155.59093, 62.88745 (WGS84)
Relative position The unnamed occurrence is located along the banks of the Kuskokwim River about 8 kilometers due south of McGrath, Alaska and 1.5 kilometers due south of VABM About, at an elevation of about 400 feet (120 m) in the SE1/4 sec. 2, T. 32 N., R. 34 W., of the Seward Meridian. The occurrence corresponds to prospect #1 of Cobb (1972) and prospect #13 of Bundtzen and Laird (1983; field no. 77BT230).

Site location context

Political divisions (FIPS codes)

Yukon-Koyukuk(Census area)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

McGrath D-6(quadrangle 1:63,360 scale)

McGrath NW(quadrangle 1:100,000 scale)

McGrath(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Stony River(hydrologic unit)

Upper Kuskokwim River(hydrologic accounting unit)

Southwest(hydrologic subregion)

Alaska(hydrologic region)

Federal lands

MTNT, Limited(ANCSA Village)

ANCSA Village NTVPIC(Type of land area)

NTVPIC(Federal land areas administered by NTVPIC)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Silver Primary
Copper Primary
Lead Primary
Nickel Critical Secondary

Materials information

Materials Type of material
Pyrite Ore
Pyrrhotite Ore
Quartz Gangue

Alteration

  • (Local) Ferricrete oxidation of pyrite and pyrrhotite.

Mineral occurrence model information

Model code 85
USGS model code 22c
Deposit model name Polymetallic veins
Mark3 model number 46

Nearby scientific data

(1) -155.59093, 62.88745

Economic information

Comments on the geologic information

  • Geologic Description = This occurrence consists of pyrite-pyrrhotite nodules in highly deformed, sheared shale and siltstone of the Late Cretaceous Kuskokwim Group (Bundtzen and Laird, 1983). Individual sulfide nodules average about 8 centimeters in diameter, and are locally oxidized to ferricrete gossan. The sulfide bearing zone, which appears to be parallel to steeply dipping bedding in the host sedimentary rocks, is about 3 meters thick. The sulfide zone quickly extends upward into the vegetated slopes (Bundtzen and Laird, 1983). Cobb (1972) and Brooks and Martin (1921) refer to the occurrence as an unnamed, copper-nickel lode. A selected grab sample reported by Bundtzen and Laird (1983) contains 12.26 grams/tonne silver, 116 ppm copper, 167 ppm lead, and 139 ppm nickel.

Economic information about the deposit and operations

Development status Occurrence

Comments on exploration

  • Status = Inactive

Mining district

District name McGrath

Comments on the workings information

  • Workings / Exploration = Brooks and Martin (1921) first mentioned the existence of sulfide mineralization at the site. A selected grab sample reported by Bundtzen and Laird (1983) contains 12.26 grams/tonne silver, 116 ppm copper, 167 ppm lead, and 139 ppm nickel.

Reference information

Bibliographic references

Comments on the references

  • Primary Reference = Bundtzen and Laird, 1983

General comments

Subject category Comment text
Deposit Model Name = Polymetallic veins (Cox and Singer, 1986; model 22c).

Reporter information

Type Date Name Affiliation Comment
Reporter 25-NOV-98 T.K. Bundtzen Pacific Rim Geological Consulting

Beyond USGS

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

Authoritative Alaska resources

These are landing pages for further research — the state agencies don't currently expose per-mine deep links.