Fidalgo-Alaska

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

Geologic information

Identification information

Deposit ID 10307363
Record type Site
Current site name Fidalgo-Alaska
Alternate or previous names Schlosser

Geographic coordinates

Geographic coordinates: -146.41953, 60.77359 (WGS84)
Relative position The Fidalgo-Alaska mine is at an elevation of about 500 feet, about 0.8 mile east of the mouth of Irish Cove and 0.5 mile north of peak 1430. It is in the NW1/4 sec. 2, T. 13 S., R. 7 W., of the Copper River Meridian. The site is accurately located to within 1000 ft. This mine is shown as site C-28 in Jansons and others (1984) and site #19 in Cobb (1972: MF-392).
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Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Copper Primary
Zinc Primary
Silver Secondary
Gold Secondary

Materials information

Materials Type of material
Chalcopyrite Ore
Pyrite Ore
Pyrrhotite Ore
Sphalerite Ore
Calcite Gangue
Quartz Gangue

Mineral occurrence model information

Model code 91
USGS model code 24b
Deposit model name Massive sulfide, Besshi (Japanese deposits)
Mark3 model number 30

Nearby scientific data

(1) -146.41953, 60.77359

Comments on the geologic information

  • Geologic Description = This deposit consists of sulfide-bearing quartz-calcite veins in 150- to 300-foot-wide shear zones in folded and sheared slate and graywacke of the Tertiary Orca Group (Nelson and others, 1985). The sulfide minerals include chalcopyrite, pyrite, pyrrhotite, and sphalerite. This mine was developed and productive from 1913 to about 1920 (Cobb, 1979: OF 79-973). Five adits with the following lengths are reported (Jansons and others, 1984): 1800 ft., 540 ft., 410 ft., 250 ft., and 50 ft. U.S Bureau of Mines samples from various adit levels and of surface materials contained 0.02% to 19.5% Cu, 150 ppm to 29% Zn, 2 ppm to 15 ppm Ag, and <0.02 ppm to 5.8 ppm Au. Industry evaluation of the property was undertaken in 1986 (B. Ellis, personal commun., 2000).
  • Age = Early Tertiary age based on the age of the host rocks (Nelson and others, 1985).

Economic information

Economic information about the deposit and operations

Development status Past Producer

Comments on exploration

  • Status = Inactive

Mining district

District name Copper River

Comments on the production information

  • Production Notes = 4,160,820 lbs. Cu and 1,384 oz Ag were produced from 21,434 tons of ore. Average grade was 10% Cu.

Comments on the reserve resource information

  • Reserves = Jansons and others (1984) report indicated reserves of 25,625 tons @ 3% Cu and inferred reserves of 224,000 tons @ 3.18% Cu.

Comments on the workings information

  • Workings / Exploration = This mine was developed and productive from 1913 to about 1920 (Cobb, 1979: OF 79-973). Five adits with the following lengths are reported (Jansons and others, 1984): 1800 ft., 540 ft., 410 ft., 250 ft., and 50 ft. U.S Bureau of Mines samples from various adit levels and of surface materials contained 0.02% to 19.5% Cu, 150 ppm to 29% Zn, 2 ppm to 15 ppm Ag, and <0.02 ppm to 5.8 ppm Au. Industry evaluation of the property was undertaken in 1986 (B. Ellis, personal commun., 2000).

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Alaska Resource Data File ARDF CV028

Bibliographic references

  • Deposit

    Jansons, Uldis, Hoekzema, R.B., Kurtak, J.M., and Fechner, S.A., 1984, Mineral occurrences in the Chugach National Forest, Southcentral Alaska: U.S. Bureau of Mines Open-File Report 5-84, 218 p., 2 sheets, scale 1:250,000.

  • Deposit

    Crowe, D.E., Nelson, S.W., Brown, P.E., Shanks III, W.C., and Valley, J.W., 1992, Geology and geochemistry of volcanogenic massive sulfide deposits and related igneous rocks, Prince William Sound, south-central Alaska: Economic Geology, v. 87, p. 1722-1746.

  • Deposit

    Crowe, D.E., Nelson, S.W., Brown, P.E., Shanks III, W.C., and Valley, J.W., 1993, Geology and geochemistry of volcanogenic massive sulfide deposits and related igneous rocks, Prince William Sound, south-central Alaska-A reply: Economic Geology, v. 88, p. 1285-1288.

  • Deposit

    Sainsbury, C.L., 1993, Geology and geochemistry of volcanogenic massive sulfide deposits and related igneous rocks, Prince William Sound, south-central Alaska, A discussion: Economic Geology, v. 88, p. 1284-1285.

  • Deposit

    Cobb, E.H., 1972, Metallic mineral resources map of the Cordova quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-392, 1 sheet, scale 1:250,000.

  • Deposit

    Cobb, E.H., 1979, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Cordova quadragle, Alaska: U.S. Geological Survey Open-file Report OF 79-973, 73 p.

  • Deposit

    Nelson, S.W., Dumoulin, J. A., and Miller, M.L., 1985, Geologic map of the Chugach National Forest, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-1645-B, 16 p., 1 sheet, scale 1:250,000.

Comments on the references

  • Primary Reference = Jansons and others, 1984

General comments

Subject category Comment text
Deposit Model Name = Besshi massive sulfide (Cox and Singer, 1986; model 24b)
Deposit Other Comments = Crowe and others (1992; 1993) and Sainsbury (1993) discuss the genesis of the volcanogenic massive sulfide deposits in this area.. Chugach Alaska Corporation, Anchorage, Alaska has control of these lands.

Reporter information

Type Date Name Affiliation Comment
Reporter 10-JUN-00 S.W. Nelson U.S. Geological Survey