Johnston & Degan

Prospect in Alaska, United States with commodities Silver, Gold, Lead

Geologic information

Identification information

Deposit ID 10000411
MRDS ID A010576
Record type Site
Current site name Johnston & Degan
Alternate or previous names Grubstake & Lost Boys
Related records 10282843

Geographic coordinates

Geographic coordinates: -150.49253, 59.51949 (WGS84)
Relative position The prospect is located on both sides of the ridge that separates Quartz Bay from Surprise Bay, both of which are in the West Arm of Nuka Bay. This is Cobb's (1972, MF-397) location 25 and MacKevett and Holloway's (1977) location 16. Cobb (1979, OFR 80-87) summarized the relevant references to this prospect under the name Johnson and Degan. This location is accurate within half a mile.
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Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Silver Primary
Gold Primary
Lead Secondary

Materials information

Materials Type of material
Arsenopyrite Ore
Galena Ore
Gold Ore
Pyrite Ore
Quartz Gangue

Alteration

  • (Local) Extensive oxidation staining on surface outcrops. Borden and others (1991) report other veins in the Nuka Bay district show carbonization, sulfidization, sericitization, and silicification of the wall rock adjacent to the veins.

Mineral occurrence model information

Model code 273
USGS model code 36a
Deposit model name Low-sulfide Au-quartz vein
Mark3 model number 27

Host and associated rocks

  • Host or associated Host
    Rock type Sedimentary Rock > Clastic Sedimentary Rock > Siltstone
    Rock unit name Valdez Group
    Rock description Valdez Group;Valdez Group;Valdez Group

Nearby scientific data

(1) -150.49253, 59.51949

Comments on the geologic information

  • Geologic Description = Cretaceous Valdez Group graywacke host the mineralization of the Johnson and Degan prospect (Richter, 1970). Generally quartz veins are hosted in the graywacke although conglomerates are found in the area. The veins are white quartz containing few percent sulfides, although some exposures show considerable iron-staining. A single sample through a vein at an elevation of 1,000 feet, on the Surprise Bay side of the ridge, assayed 0.98 ounces of gold and 1.0 ounce of silver per ton (Pilgrim, 1933).
  • Age = Tertiary; Boden and others (1991) report other veins in the district are about 55 m.y. old.

Economic information

Economic information about the deposit and operations

Development status Prospect
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Homer

Comments on the workings information

  • Workings / Exploration = Surface trails were laid and trenches were dug in the 1930's. A single sample through a vein at 1000 feet elevation on the Surprise Bay side of the ridge, assayed 0.98 ounces of gold and 1.0 ounce of silver per ton (Pilgrim, 1933).

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A010576
USGS Alaska Resource Data File ARDF SV010

Bibliographic references

  • Deposit

    Pilgrim, E.R., 1933, Progress of lode mining in interior Alaska, 1932: Alaska Territorial Department of Mines Miscellaneous Report 194, 11 p.

  • Deposit

    Capps, S.R., 1938, Lode mining in the Nuka Bay district, in Smith, P.S., Mineral industry of Alaska in 1936: U.S. Geological Survey Bulletin 897-A, p. 25-32.

  • Deposit

    Cobb, E.H., 1972, Metallic minerals resources map of the Seldovia quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-397, 1 sheet, scale 1:250,000.

  • Deposit

    Borden, J.C., Goldfarb, R.J., Gent, C.A., Burruss, R.C., and Roushey, B.H., 1992 Geochemistry of lode-gold deposits, Nuka Bay district, southern Kenai Peninsula: Geologic studies in Alaska by the U.S. Geological Survey, 1991: U.S. Geological Survey Bulletin 2041, p. 13-21.

  • Deposit

    Cobb, E.H., 1979, Summary of references to mineral occurrences (other than minerals fuels and construction materials) in the Seldovia quadrangle, Alaska: U.S. Geological Survey Open-file Report 80-87, 47 p.

  • Deposit

    Richter, D.H., 1970, Geology and lode-gold deposits of the Nuka Bay area, Kenai Peninsula, Alaska: U.S. Geological Survey Professional Paper 625-B, p. Bl-B16.

  • Deposit

    MacKevett, E.M., Jr., and Holloway, C.D., 1977, Map showing metalliferous and selected non-metalliferous mineral deposits in the eastern part of southern Alaska: U.S. Geological Survey Open-File Report 77-169-A, 99 p., 1 sheet, scale 1:1,000,000.

Comments on the references

  • Primary Reference = Pilgrim, 1933

General comments

Subject category Comment text
Deposit Model Name = Low-sulfide, Au-quartz vein (Cox and Singer, 1986; model 36a)
Deposit Other Comments = This prospect is within the Kenai Fjords National Park; the area is closed to mineral entry.

Reporter information

Type Date Name Affiliation Comment
Reporter 09-FEB-1999 Jeff A. Huber U.S. Geological Survey