1. Mineral Resources
  2. Online Spatial Data
  3. Mineral Resource Data System (MRDS)

Unnamed (near Iceberg Point, Lemesurier Island)

Prospect in Alaska, United States with commodities Copper, Molybdenum
Map
XML
JSON
KML
B
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. Host and associated rocks
  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 10002289
MRDS ID A013193
Record type Site
Current site name Unnamed (near Iceberg Point, Lemesurier Island)

Geographic coordinates

Geographic coordinates: -136.07817, 58.26278 (WGS84)
Relative position The occurrence is almost at sea level on Iceberg Point, south of Jacks Cove and west of Willoughby Cove on the south-central coastline of Lemesurier Island. The site is location number 62 of Cobb (1972). It is accurately located within 0.15 mile.

Site location context

Political divisions (FIPS codes)

Hoonah-Angoon(Census area)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Mount Fairweather B-1(quadrangle 1:63,360 scale)

Juneau SW(quadrangle 1:100,000 scale)

Mount Fairweather(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Central Southeast Alaska(hydrologic accounting unit)

Southeast Alaska(hydrologic subregion)

Alaska(hydrologic region)

Federal lands

Tongass National Forest(National Forest)

National Forest FS(Type of land area)

FS(Federal land areas administered by FS)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Copper Primary
Molybdenum Primary

Comments on the commodity information

  • Gangue = paligorskite

Materials information

Materials Type of material
Bornite Ore
Chalcopyrite Ore
Molybdenite Ore
Calcite Gangue
Epidote Gangue
Garnet Gangue
Quartz Gangue

Alteration

  • (Local) Development of tactite in limestone.

Host and associated rocks

  • Host or associated Host
    Rock type Sedimentary Rock > Carbonate > Limestone
    Stratigraphic age (youngest) Late Silurian

Nearby scientific data

(1) -136.07817, 58.26278
ListMap

Economic information

Comments on the geologic information

  • Geologic Description = The occurrence is in limestone of Paleozoic age which, elsewhere on Lemesurier Island, is cut by granitic intrusions. The mineral suite reported at the locality--quartz, garnet, epidote, pyroxene, calcite, molybdenite, chalcopyrite, and bornite--(Smith, 1942, p. 177) is a tactite suite, probably related to a nearby intrusion. An unusual asbestos-like mineral, paligorskite, called mountain leather, formed as replacement of limestone near copper-molybdenum bearing vein occurrences. Paligorskite masses reportedly were mined by Joe Ibach. ? the site is about three-quarters of a mile east-northeast of the Whitney claims (MF079) another occurrence of copper-molybdenum minerals on the island.
  • Age = Cretaceous or younger.

Economic information about the deposit and operations

Development status Prospect
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Chichagof

Comments on the production information

  • Production Notes = Production of paligorskite, probably as mineral specimens by Ibach.

Comments on the workings information

  • Workings / Exploration = Surface exposures of copper and molybdenum minerals were explored by trenches and cuts dug by long-time southeast Alaska prospector Joe Ibach, who occasionally lived on the island. The occurrence was first reported by Buddington (1926). It was also listed by Buddington and Chapin (1929) and briefly described by Smith (1942, p. 177).

Reference information

Bibliographic references

  • Deposit

    Buddington, A.F., 1926, Mineral investigations in southeastern Alaska: U.S. Geological Survey Bulletin 783, p. 41-62.

  • Deposit

    Buddington, A.F., and Chapin, Theodore, 1929, Geology and mineral deposits of southeastern Alaska: U.S. Geological Survey Bulletin 800, 398 p.

  • Deposit

    Cobb, E.H., 1972, Metallic mineral resources map of the Mount Fairweather quadrangle, AK: U.S. Geological Survey Miscellaneous Field Study Map MF-436, 1 sheet, scale 1:250,000.

  • Deposit

    Cobb, E.H., 1978, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Mt. Fairweather and Skagway quadrangles, Alaska: U.S. Geological Survey Open-File Report 78-316, 123 p.

  • Deposit

    Smith, P.S., 1942, Occurrences of molybdenum in Alaska: U.S. Geological Survey Bulletin 926-C, p. 161-210.

Comments on the references

  • Primary Reference = Buddington, 1926; Smith, 1942

General comments

Subject category Comment text
Deposit Model Name = Distal tactite, suspected intrusion not exposed.
Deposit Other Comments = the prospect is in a carbonate terrane of Paleozoic age. The prospect is in Tongass National Forest and appears to be open for mineral location. Claim activity is unknown.

Reporter information

Type Date Name Affiliation Comment
Reporter 14-APR-99 Hawley, C.C. Hawley Resource Group

Beyond USGS

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

Maps centered on this site

Authoritative Alaska resources

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