Unnamed (near Devilfish Bay)

Prospect in Alaska, United States with commodities Copper, Molybdenum, Uranium

Geologic information

Identification information

Deposit ID 10000299
MRDS ID A010344
Record type Site
Current site name Unnamed (near Devilfish Bay)
Related records 10282627

Geographic coordinates

Geographic coordinates: -133.39075, 56.08473 (WGS84)
Relative position Prospect near the head of Devilfish Bay, northwest Kosciusko, in the NW1/4, section 8, T. 67 S., R. 78 E.
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Geographic areas

Country State
United States Alaska


Commodity Importance
Copper Primary
Molybdenum Primary
Uranium Primary

Comments on the commodity information

  • Gangue = Calcsilicate minerals in tactite

Materials information

Materials Type of material
Chalcopyrite Ore
Magnetite Ore
Molybdenite Ore


  • (Local) Calcsilicate minerals associated with intrusion of quartz monzonite into calcareous rocks.

Mineral occurrence model information

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

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Mafic Intrusive Rock > Diorite
  • Host or associated Host
    Rock type Metamorphic Rock > Skarn (Tactite)

Nearby scientific data

(1) -133.39075, 56.08473

Comments on the geologic information

  • Geologic Description = Magnetite, chalcopyrite, and minor molybdenite occur in tactite at contact between a Cretaceous quartz monzonite pluton and Cretaceous hornfels formed from calcareous graywacke of the Silurian Bay of Pillars Formation (Herreid and Kaufman, 1964, p. 4; Eakins, 1975, p. 54-57; and Brew and others, 1984). One sample of the tactite contained 8 ppm equivalent uranium.
  • Age = Related to intrusion of Cretaceous quartz monzonite pluton.

Economic information

Economic information about the deposit and operations

Development status Prospect
Commodity type Metallic

Comments on exploration

  • Status = Probably inactive

Mining district

District name Ketchikan

Comments on the production information

  • Production Notes = None

Comments on the reserve resource information

  • Reserves = None

Comments on the workings information

  • Workings / Exploration = Only work noted in 1975 was a single, hand-dug pit; little indication of any work since. But see PE053 for several blocks of claims staked around this prospect and active through at least 1981.

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A010344
USGS Alaska Resource Data File ARDF PE052

Bibliographic references

  • Deposit

    Herreid, G.H., and Kaufman, M. A., 1964, Geology of the Dry Pass area, southeastern Alaska: Alaska Division of Mines and Minerals Geologic Report 7, 16 p.

  • Deposit

    Eakins, G.R., 1975, Uranium investigations in southeastern Alaska: Alaska Division of Geological and Geophysical Surveys Geologic Report 44, 62 p.

  • Deposit

    Cobb, E.H., 1978, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Petersburg quadrangle, Alaska: U.S. Geological Survey Open-File Report 78-870, 53 p.

  • Deposit

    Cobb, E.H., 1972, Metallic mineral resources map of the Petersburg quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-415, 1 sheet, scale 1:250,000.

  • Deposit

    Brew, D. A., Ovenshine, A. T., Karl, S. M., and Hunt, S. J., 1984, Preliminary reconnaissance geologic map of the Petersburg and parts of the Port Alexander and Sumdum 1:250,000 quadrangles, southeastern Alaska: U.S. Geological Survey Open-File Report 84-405, 43 p., 2 sheets, scale 1:250,000.

  • Deposit

    Grybeck, D.J., Berg, H.C., and Karl, S.M., 1984, Map and description of the mineral deposits in the Petersburg and eastern Port Alexander quadrangles: U.S. Geological Survey Open-File Report 84-837, 86 p., 1 sheet, scale 1:250,000.

  • Deposit

    Maas, K.M., Bittenbender, P E., and Still, J.C., 1995, Mineral investigations in the Ketchikan mining district, southeastern Alaska: U.S. Bureau of Mines Open-File Report 11-95, 606 p.

  • Deposit

    Herreid, G.H., and Kaufman, M. A., 1964, Geology of the Dry Pass area, southeastern Alaska: Alaska Division of Mines and Minerals Geologic Report 7, 12 p.

Comments on the references

  • Primary Reference = Herreid and Kaufman, 1964

General comments

Subject category Comment text
Deposit Model Name = Cu-Mo skarn with uranium?(Cox and Singer, 1986; model 18b)

Reporter information

Type Date Name Affiliation Comment
Reporter 01-NOV-1998 H.C. Berg U.S. Geological Survey
Reporter 01-NOV-1998 D.J. Grybeck U.S. Geological Survey