Unnamed (in the northern Chilkat Range)

Occurrence in Alaska, United States with commodities Silver, Copper, Cobalt
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 10308239
Record type Site
Current site name Unnamed (in the northern Chilkat Range)

Geographic coordinates

Geographic coordinates: -135.7221, 59.14974 (WGS84)
Relative position This occurrence is at an elevation of about 5,000 feet about 3.7 miles, S87W from triangulation station 'Bow' on the west side of Chilkat Inlet. It is in the SW1/4, section 25, T. 31 S., R. 58 E. of the Copper River Meridian and is in a narrow septum of rock between two unnamed ice fields. The location corresponds to location 68 of Gilbert (1988).

Site location context

Political divisions (FIPS codes)

Haines(Borough)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Skagway A-2(quadrangle 1:63,360 scale)

Skagway SE(quadrangle 1:100,000 scale)

Skagway(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Chilkat-Skagway Rivers(hydrologic unit)

Northern Southeast Alaska(hydrologic accounting unit)

Southeast Alaska(hydrologic subregion)

Alaska(hydrologic region)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Silver Primary
Copper Primary
Cobalt Critical Secondary

Materials information

Materials Type of material
Chalcopyrite Ore
Pyrite Ore
Pyrrhotite Ore
Quartz Gangue

Alteration

  • (Local) Skarn.

Mineral occurrence model information

Model code 59
USGS model code 18b
Deposit model name Skarn Cu
Mark3 model number 8

Nearby scientific data

(1) -135.7221, 59.14974

Economic information

Comments on the geologic information

  • Geologic Description = Gilbert (1988) collected four rock samples described as, 'skarn with pyrrhotite (60%) and chalcopyrite', 'gossan with pyrrhotite', 'black schist with pyrrhotite (20%)', and 'quartz with pyrite in shear'. The samples contain up to 4.6 ppm silver, 5,950 ppm copper, and 95 ppm cobalt. The host rocks are mafic Paleozoic metavolcanics and metasediments that include argillaceous marble. Cretaceous medium-grained hornblende diorite and foliated granodiorite are nearby (Gilbert, 1988). The mineralization is probably the same age as the nearby Cretaceous intrusive rocks.
  • Age = the age is inferred to be Cretaceous based upon the Cretaceous age of nearby intrusive rocks (Gilbert, 1988).

Economic information about the deposit and operations

Development status Occurrence

Comments on exploration

  • Status = Probably inactive

Mining district

District name Juneau (Skagway subdistrict)

Reference information

Comments on the references

  • Primary Reference = Gilbert, 1988

General comments

Subject category Comment text
Deposit Model Name = Copper skarn? (Cox and Singer, 1986: model 18b?)

Reporter information

Type Date Name Affiliation Comment
Reporter 04-FEB-01 T.C. Crafford T. Crafford & Associates

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.