Reynolds-Alaska Development Co.

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

Geologic information

Identification information

Deposit ID 10000371
MRDS ID A010438
Record type Site
Current site name Reynolds-Alaska Development Co.
Related records 10209922

Geographic coordinates

Geographic coordinates: -146.6306, 60.88265 (WGS84)
Relative position The map site of this mine is at the position of the main tunnel, which is at sea level on the east side of Boulder Bay. The site is in the S1/2 sec. 27, T. 11 S., R 8 W., of the Copper River Meridian. The location is accurate to within 1000 ft. This mine is shown as #7 in Cobb (1972: MF-392) and as C-87 in Jansons and others (1984).
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Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Copper Primary
Zinc Primary
Silver Secondary

Materials information

Materials Type of material
Chalcopyrite Ore
Pyrrhotite Ore
Sphalerite Ore

Mineral occurrence model information

Model code 90
USGS model code 24a
Deposit model name Massive sulfide, Cyprus
Mark3 model number 11

Host and associated rocks

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

Nearby scientific data

(1) -146.6306, 60.88265

Comments on the geologic information

  • Geologic Description = The country rocks at this mine are mafic volcanic rocks and sedimentary rocks of the Tertiary Orca Group (Nelson and others, 1985). The deposit consists of massive sulfide lenses, and sulfide veins, disseminations, and thin selvages in shear zones (Jansons and others,1984). The sulfide minerals are chalcopyrite, pyrrhotite, and sphalerite. The ore minerals are restricted to north-trending and steeply-dipping shears at the contact of volcanic and sedimentary rock.? Grant and Higgins (1909) report that some large beach boulders were shipped as ore. Chip samples collected in the 1980s contained 0.6 to 1.7% Cu, 225 ppm to 0.61% Zn, and 2.4 ppm to 8.9 ppm Ag; grab samples contained 60 ppm to 6% Cu, 67 ppm to 1.7% Zn, and 1.1 ppm to 13 ppm Ag (Jansons and others, 1984).
  • Age = Probably Tertiary based on the age of the host rocks.

Economic information

Economic information about the deposit and operations

Development status Past Producer
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Copper River

Comments on the production information

  • Production Notes = 215,000 lbs. Cu were recoverd from 2,850 tons of ore (Jansons and others, 1984).

Comments on the reserve resource information

  • Reserves = Inferred reserves of 600 tons @ 1.37% Cu, 0.28% Zn, and 6.67 ppm Ag (Jansons and others, 1984).

Comments on the workings information

  • Workings / Exploration = The mine was developed in the early 1900s by 2100 feet of drifts (main tunnel), numerous crosscuts, winzes and raises, and at least 500 ft. of additional tunnels (Capps and Johnson, 1915). One 200 ft. tunnel was caved by the early 1980s (Jansons and others, 1984). Grant and Higgins (1909) report that some large beach boulders were shipped as ore. Chip samples collected in the 1980s contained 0.6 to 1.7% Cu, 225 ppm to 0.61% Zn, and 2.4 ppm to 8.9 ppm Ag; grab samples contained 60 ppm to 6% Cu, 67 ppm to 1.7% Zn, and 1.1 ppm to 13 ppm Ag (Jansons and others, 1984).

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A010438
USGS Alaska Resource Data File ARDF CV007

Bibliographic references

  • Deposit

    Capps, S.R., and Johnson, B.L., 1915, The Ellamar district, Alaska: U.S. Geological Survey Bulletin 605, 125 p.

  • 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

    Grant, U.S., and Higgins, D.F., Jr., 1909, Copper mining and prospecting on Prince William Sound: U.S. Geological Survey Bulletin 379-C, p. 87-96.

  • 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

    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 = Cyprus massive sulfide (Cox and Singer, 1986; model 24a)
Deposit Other Comments = Nelson and others (1985) interpret the country rocks as accreted ocean crust. 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