Golden Eagle

Producer in Alaska, United States with commodities Gold, Silver, Zinc

Geologic information

Identification information

Deposit ID 10107534
MRDS ID A013081
Record type Site
Current site name Golden Eagle
Alternate or previous names McKinley Creek, Vug
Related records 10282944

Geographic coordinates

Geographic coordinates: -136.22213, 59.36974 (WGS84)
Relative position This small mine is located at an elevation of between 1,820 and 1,850 feet on the west bank of McKinley Creek, about 2 miles above its junction with Porcupine Creek. it is shown as location 106 by Still and others (1984).
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Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Gold Primary
Silver Secondary
Zinc Secondary

Comments on the commodity information

  • Gangue = native sulfur

Materials information

Materials Type of material
Arsenopyrite Ore
Gold Ore
Pyrite Ore
Pyrrhotite Ore
Sphalerite Ore
Quartz Gangue

Alteration

  • (Local) The silica-carbonate units which are cut by or parallel the quartz-sulfide veins are probably altered mafic dikes (Still and others, 1991). Questionable mariposite, which may result from the alteration of mafic minerals, is also described (Bundtzen and Clautice, 1986).

Mineral occurrence model information

Model code 85
USGS model code 22c
Deposit model name Polymetallic veins
Mark3 model number 46

Host and associated rocks

  • Host or associated Host
    Rock type Metamorphic Rock > Metasedimentary Rock > Slate
    Rock unit name Porcupine Slate;Porcupine Slate;Porcupine Slate;Porcupine Slate
    Rock description Porcupine Slate;Porcupine Slate;Porcupine Slate;Porcupine Slate

Nearby scientific data

(1) -136.22213, 59.36974

Comments on the geologic information

  • Geologic Description = The following is summarized from Bundtzen and Clautice (1986). In the vicinity of the Golden Eagle occurrence, the Porcupine Slate that host this prospect is a dark-gray, pyrite-rich, micaceous, carbonaceous slate to phyllite, with minor siltstone and metasandstone. Tan to brown, micaceous silica-carbonate bands are either beds or altered mafic dikes. The Golden Eagle lode is a quartz-pyrite-pyrrhotite-sphalerite fissure vein that cuts a 11- to 15-foot-wide, tan, silica-carbonate band. On the west side of McKinley Creek, the vein ranges from 3 inches to 27 inches thick, strikes N35-65W, and dips steeply northeast to vertical. The hanging wall of the vein contains a highly gossanous 3.5-foot-long by 0.5 to -1-foot wide wedge of bronze-colored pyrite, pyrrhotite, and minor sphalerite. Oxidation of the sulfides has left a vug of euhedral quartz crystals, ferricrete gossan, and local concentrations of very fine-grained free gold. Native sulfur spheres and masses up to 2 inches in diameter envelope clots of sulfide grains, particularly sphalerite. Vertically higher on the vein exposure, smaller pods of massive to disseminated pyrite, pyrrhotite, and minor sphalerite are localized along the hanging wall. The average sulfide content of the vein is only 5% to 8%. At least two phases of silica injection are apparent. The weighted average of six samples taken along 14 feet of exposed vein is 0.653 ounce of gold per ton, 0.227 ounces of silver per ton, and 0.45% zinc, with traces of copper, lead, and cobalt. Grab samples of five similar, smaller, quartz-sulfide veins downstream from the Golden Eagle lode averaged 0.495 ounce of gold per ton, and 0.043% zinc, with traces of cobalt, copper, and lead.? Still and others (1991) assert that the silica-carbonate bands are altered dikes of original mafic composition. Most of the quartz veins are transverse fracture fillings confined to the silica-carbonate-altered dikes.? This small mine is within the northwest-trending zone of quartz-sulfide veining in sediments and slates in the Skagway B-4 quadrangle that is described by Wright (1904 [B 225 and B 236]), Eakin (1918 and 1919), and MacKevett and others (1974) and considered to be the source of placer gold in the area. These particular veins are probably one of the major gold sources for the McKinley Creek placer deposit (SK045) as little placer gold is found above this lode deposit.
  • Age = Unknown, but probably Cretaceous or younger based on the age of intrusives in area (MacKevett and others, 1974).

Economic information

Economic information about the deposit and operations

Development status Producer
Commodity type Metallic

Comments on exploration

  • Status = Active?

Mining district

District name Juneau (Skagway subdistrict)

Comments on the production information

  • Production Notes = Over 150 pounds of sulfides were reported mined from a large vug on the Vug vein from about 1983 to 1985 with the recovery of about 0.5 troy ounces of gold (Still and others, 1991).

Comments on the reserve resource information

  • Reserves = Still and others (1991) concluded that, 'Except for the Vug vein, the 30 or so quartz ladder veins examined on this prospect are not large enough or close enough to be considered for mine development.' 'The Vug vein may indicate potential for isolated spots of high-grade gold mineralization...', '...values in the quartz veins do encourage further exploration for faults or other structures...', and 'The gold values in the slate suggest a possibility of low-grade large-volume gold mineralization.'

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A013081
USGS Alaska Resource Data File ARDF SK047

Bibliographic references

  • Deposit

    Wright, C.W., 1904, The Porcupine placer mining district, Alaska in Emmons, S.F., and Hayes, C.W., eds., Contributions to economic geology 1903: U.S. Geological Survey Bulletin 225, p.60-63.

  • Deposit

    Wright, C.W., 1904, The Porcupine district, Alaska: U.S. Geological Survey Bulletin 236, 35 p.

  • Deposit

    Eakin, H.M., 1919, The Porcupine gold placer district, Alaska: U.S. Geological Survey Bulletin 699, 29 p.

  • Deposit

    MacKevett, E.M., Jr., Robertson, E.C., and Winkler, G.R., 1974, Geology of the Skagway B-3 and B-4 quadrangles, southern Alaska: U.S. Geological Survey Professional Paper 832, 33 p.

  • Deposit

    Still, J.C., Weir, K.R., Gilbert, W.G., and Redman, E.C., 1984, Stream-sediment, float, and bedrock sampling in the Porcupine mining area, southeast Alaska: U.S. Bureau of Mines Open-File Report 173-84, 19 p.

  • Deposit

    Bundtzen, T.K., and Clautice, K.H., 1986, Prospect examination of the Golden Eagle lode-gold prospect near Porcupine, Skagway B-4 Quadrangle, Alaska: Alaska Division of Geological and Geophysical Surveys Public-Data File 86-18, 7 p.

  • Deposit

    Hoekzema, R.B., Fechner, S.A., and Bundtzen, T.K., 1986, Distribution, analysis, and recovery of placer gold from the Porcupine mining area, southeast Alaska: U.S. Bureau of Mines Open-File Report 89-86, 49 p., 4 sheets.

  • Deposit

    Still, J.C., 1991, Bureau of Mines mineral investigations in the Juneau mining district, Alaska, 1984 - 1988, v. 2, Detailed mine, prospect, and mineral occurrence descriptions, section A, Haines-Klukwan-Porcupine subarea: U.S. Bureau of Mines of Mines Special Publication, 214 p.

  • Deposit

    Still, J.C., Hoekzema, R.B., Bundtzen, T.K., Gilbert, W.G., Wier, K.R., Burns, L.E., and Fechner, S.A., 1991, Economic geology of Haines-Klukwan-Porcupine area, southeastern Alaska: Alaska Division of Geological and Geophysical Surveys Report of Investigations 91-4, 156 p., 5 sheets, scale 1:63,360.

  • Deposit

    Eakin, H.M., 1918, Gold placer mining in the Porcupine district: U.S. Geological Survey Bulletin 662-B, p. 93-100.

Comments on the references

  • Primary Reference = Bundtzen and Clautice, 1986

General comments

Subject category Comment text
Deposit Model Name = Auriferous quartz-sulfide vein (Cox and Singer, 1986; model 22c).

Reporter information

Type Date Name Affiliation Comment
Reporter 04-FEB-2001 T.C. Crafford T. Crafford & Associates