Dickey Copper Co.; Mason & Gleason Co. Mine, Copper River Mining District, Valdez-Cordova Census Area, Alaska, USAi

Regional Level Types
Dickey Copper Co.; Mason & Gleason Co. Mine	Mine
Copper River Mining District	Mining District
Valdez-Cordova Census Area	Census Area
Alaska	State
USA	Country

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.
Location: 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).
Geology: 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 commun., 2000). Jansons and others (1984) report the following analyses: Five grab samples from the 500 ft. adit contained 0.01% to 1.23% Cu, 0.02% to 1.5% Zn, <0.03 ppm to 12.5 ppm Au, <0.01 ppm to 28 ppm Ag, and 0.01 to 0.13% 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% Cu, 1.43% to 14% Zn, <0.03 ppm to 5.25 ppm Au, 25 to 26 ppm Ag, 80 ppm to 0.13% Pb, and 14 ppm to 740 ppm Co. A grab sample from the crosscut contained 1.6% Cu, 3.1% Zn, 2.8 ppm Au and 10 ppm Ag. A 262-pound bulk sample from the ore bunkers contained 8.65% Cu, 9.6% Zn, 0.072 oz. Au/ton, 0.62 oz. Ag/ton, and 0.04% Co.
Workings: 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 commun., 2000). Jansons and others (1984) report the following analyses: Five grab samples from the 500 ft. adit contained 0.01% to 1.23% Cu, 0.02% to 1.5% Zn, <0.03 ppm to 12.5 ppm Au, <0.01 ppm to 28 ppm Ag, and 0.01 to 0.13% 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% Cu, 1.43% to 14% Zn, <0.03 ppm to 5.25 ppm Au, 25 to 26 ppm Ag, 80 ppm to 0.13% Pb, and 14 ppm to 740 ppm Co. A grab sample from the crosscut contained 1.6% Cu, 3.1% Zn, 2.8 ppm Au and 10 ppm Ag. A 262-pound bulk sample from the ore bunkers contained 8.65% Cu, 9.6% Zn, 0.072 oz. Au/ton, 0.62 oz. Ag/ton, and 0.04% Co.
Age: Probably Tertiary based on the age of the host rocks (Crowe and others, 1992).
Production: 29,346 pounds of copper was produced, mainly in 1917.
Reserves: Moffit and Fellows (1950) report that geophysical prospecting suggests that the mines in this area (CV028 and CV029) contain additional undiscovered mineral resources.

Commodities (Major) - Au, Cu; (Minor) - Ag, Co, Pb, Zn
Development Status: Yes; small
Deposit Model: Besshi massive sulfide (Cox and Singer, 1986: model 24b)

Other Databases

Link to USGS - Alaska:	CV029

Other Regions, Features and Areas containing this locality

References