Iron Bridge

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

Geologic information

Identification information

Deposit ID 10308258
Record type Site
Current site name Iron Bridge

Geographic coordinates

Geographic coordinates: -136.11214, 59.54975 (WGS84)
Relative position This prospect is approximately 3/4 mile north-northwest of the junction of Nataga Creek and the Kelsall River. It is in the NW1/4, section 8, T. 27 S., R. 55 E. of the Copper River Meridian. It is shown as location 3 by Still and others (1991) and as location 28 by Gilbert and others (1991).

Site location context

Political divisions (FIPS codes)

Haines(Borough)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Skagway C-3(quadrangle 1:63,360 scale)

Skagway NE(quadrangle 1:100,000 scale)

Skagway C(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
Gold Primary
Copper Primary

Materials information

Materials Type of material
Malachite Ore
Sphalerite Ore

Nearby scientific data

(1) -136.11214, 59.54975

Economic information

Comments on the geologic information

  • Geologic Description = This prospect consists of malachite-stained silicified rocks that occur in metamorphosed volcanic and sedimentary rocks (Still and others, 1991). Gilbert and others (1991) reported samples that contained up to 0.041 ppm gold, 5.6 ppm silver, and 2,960 ppm copper. There is very little information about this prospect. Mapping to the east by Gilbert and others (1990) suggests that the metamorphosed volcanic and sedimentary rocks described by Still and others (1991) are a roof pendant within Cretaceous to Tertiary intrusive rocks that are part of the Coast Range batholith.
  • Age = Unknown. The mineralization may be related to Cretaceous to Tertiary plutonic bodies mapped to the east by Gilbert and others (1990).

Economic information about the deposit and operations

Development status Prospect

Comments on exploration

  • Status = Probably inactive

Mining district

District name Juneau (Skagway subdistrict)

Comments on the workings information

  • Workings / Exploration = In the 1970's, Mr. Jones, a local prospector, prospected cuts in a newly built logging road. Shallow trenches and stockpiles of malachite-stained silicified rocks were discovered in this thickly overgrown area in 1988 (Still and others, 1991).

Reference information

Comments on the references

  • Primary Reference = Still and others, 1991

General comments

Subject category Comment text
Deposit Model Name = Too little information to assign a model type.
Deposit Other Comments = This prospect is immediately west of the Alaska, Chilkat Bald Eagle Preserve.

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.