Dickey Copper Co. (ARDF #CV029) Au, Cu

Dickey Copper Co.

Mine, Inactive

Alternative names

Mason & Gleason Co.

Commodities and mineralogy

Main commodities	Au; Cu
Other commodities	Ag; Co; Pb; Zn
Ore minerals	chalcopyrite; pyrite; pyrrhotite; sphalerite
Gangue minerals	calcite; quartz

Geographic location

Quadrangle map, 1:250,000-scale	CV
Quadrangle map, 1:63,360-scale	D-7
Latitude	60.77
Longitude	-146.41
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	This mine is at an elevation of about 500 feet about 1.3 miles east of Irish Cove, and 0.5 mile southeast of peak 1430. It is in the S1/2 sec. 2, T. 13 S., R. 7 W., of the Copper River Meridian. The location is accurate within 2000 ft. The mine is about 0.25 mile east of its position shown as site C-65 in Jansons and others (1984) (B. Ellis, personal commun., 2000).

Geologic setting

Geologic description This deposit consists of sulfide-bearing quartz-calcite veins in 6- to 8-foot-wide shear zones in slate and graywacke of the Tertiary Orca Group (Nelson and others, 1985). The sulfide minerals include chalcopyrite, pyrite, pyrrhotite, and sphalerite. The mine was active in the period 1910-1913, but most of the production was in 1917 (Moffit and Fellows, 1950). Two principal adits at 470 ft. and 540 ft. were connected by raises. There reportedly were additional crosscuts and drifts (Moffit and Fellows, 1950). Jansons and others (1984) report four adits having the following lengths: 500 ft., 125 ft., 35 ft. (caved), and 10 ft. There was some industry reevaluation in 1986 (B. Ellis, personal communication, 2000). Jansons and others (1984) report the following analyses: Five grab samples from the 500 ft. adit contained 0.01 to 1.23 percent Cu, 0.02 to 1.5 percent Zn, <0.03 ppm to 12.5 ppm Au, <0.01 ppm to 28 ppm Ag, and 0.01 to 0.13 percent Pb. A selected grab sample contained 15.5 ppm Au. Five grab samples from the 125-ft.-long adit contained 0.3 to 4.3 percent Cu, 1.43 to 14 percent Zn, <0.03 ppm to 5.25 ppm Au, 25 to 26 ppm Ag, 80 ppm to 0.13 percent Pb, and 14 ppm to 740 ppm Co. A grab sample from the crosscut contained 1.6 percent Cu, 3.1 percent Zn, 2.8 ppm Au and 10 ppm Ag. A 262-pound bulk sample from the ore bunkers contained 8.65 percent Cu, 9.6 percent Zn, 0.072 oz. Au/ton, 0.62 oz. Ag/ton, and 0.04 percent Co.
Geologic map unit	(-146.411971048799, 60.7694442428857)
Mineral deposit model	Besshi massive sulfide (Cox and Singer, 1986: model 24b)
Mineral deposit model number	24b
Age of mineralization	Probably Tertiary based on the age of the host rocks (Crowe and others, 1992).

Production and reserves

Workings or exploration	The mine was active in the period 1910-1913, but most of the production was in 1917 (Moffit and Fellows, 1950). Two principal adits at 470 ft. and 540 ft. were connected by raises. There reportedly were additional cross cuts and drifts (Moffit and Fellows, 1950). Jansons and others (1984) report four adits having the following lengths: 500 ft., 125 ft., 35 ft. (caved), and 10 ft. There was some industry reevaluation in 1986 (B. Ellis, personal communication, 2000). Jansons and others (1984) report the following analyses: Five grab samples from the 500 ft. adit contained 0.01 to 1.23 percent Cu, 0.02 to 1.5 percent Zn, <0.03 ppm to 12.5 ppm Au, <0.01 ppm to 28 ppm Ag, and 0.01 to 0.13 percent Pb. A selected grab sample contained 15.5 ppm Au. Five grab samples from the 125-ft.-long adit contained 0.3 to 4.3 percent Cu, 1.43 to 14 percent Zn, <0.03 ppm to 5.25 ppm Au, 25 to 26 ppm Ag, 80 ppm to 0.13 percent Pb, and 14 ppm to 740 ppm Co. A grab sample from the crosscut contained 1.6 percent Cu, 3.1 percent Zn, 2.8 ppm Au and 10 ppm Ag. A 262-pound bulk sample from the ore bunkers contained 8.65 percent Cu, 9.6 percent Zn, 0.072 oz. Au/ton, 0.62 oz. Ag/ton, and 0.04 percent Co.
Indication of production	Yes; small
Reserve estimates	Moffit and Fellows (1950) report that geophysical prospecting suggests that the mines in this area (CV028 and CV029) contain additional undiscovered mineral resources.
Production notes	29,346 pounds of copper was produced, mainly in 1917.
Additional 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.

References

MRDS Number	A010426
References Crowe, D.E., Nelson, S.W., Brown, P.E., Valley, J.W., and Shanks, W.C., III, 1992, Geology and geochemistry of volcanogenic massive sulfide deposits and related igneous rocks, Prince William Sound region, south-central Alaska: Economic Geology, v. 87, no. 7, p. 1722-1746. Crowe, D.E., Nelson, S.W., Brown, P.E., Valley, J.W., and Shanks, W.C., III, 1993, Geology and geochemistry of volcanogenic massive sulfide deposits and related igneous rocks, Prince William Sound, south-central Alaska--Reply: Economic Geology, v. 88, p. 1285-1288. 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 Mineral Land Assessment 5-84, 218 p., 2 sheets, scale 1:250,000. Moffit, F.H., and Fellows, R.E., 1950, Coper deposits of the Prince William Sound district, Alaska: U.S. Geological Survey Bulletin 963-B, p. 47-80. 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. 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.
Reporters	S.W. Nelson, Anchorage, AK
Last report date	6/10/2000