|Quadrangle map, 1:250,000-scale||VA|
|Quadrangle map, 1:63,360-scale||A-8|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This mine is 1.7 miles west of Mount Cameron on the east end of a nunatak in the eastern part of Columbia Glacier; it is at an elelvation of about 3,600 feet in the NW1/4 of section 6, T. 8 S., R. 8 W., of the Copper River Meridian. This mine is located to within one-quarter mile. It is locality 2 of Cobb and Matson (1972) and locality 2 of Winkler and others (1981 [OFR 80-892-B]).|
The Gold King mine consists of gold-bearing quartz veins that cut metaflysch of the Valdez Group (Johnson, 1915). The principal vein strikes northwest and dips 50 to 60 degrees south; it is as much as a few feet thick but averages about one foot in thickness. Gouge is developed along one wall and merges into quartz stringer zones in shattered metagraywacke. The quartz veins contain calcite, a cream-colored carbonate mineral, and about 3 per cent sulfides including pyrite, galena, chalcopyrite, sphalerite, and stibnite (Johnson, 1915). The veins were developed by three adits and more than 2,000 feet of underground workings (Johnson, 1915; Cobb, 1979 [OFR 79-1241]; Jansons and others, 1984). A mill was installed on site. and total reported production between 1911 and 1922 was 1,997 ounces of gold and 187 ounces of silver from 1,560 tons of ore (Hoekzema and others, 1986). The average grade indicated by this production is about 1.3 ounces of gold per ton. The U.S. Bureau of Mines collected five chip samples from the area of these deposits that contained 0.09 to 3.4 ppm gold and 0.1 to 1.3 ppm silver; two grab samples contained 4.85 and 45.62 ounces of gold and 1.0 to 1.7 ounces of silver per ton. Six other samples contained as much as 9 ppm gold (Pickthorn, 1982).These deposits are probably similar to other gold-bearing quartz veins cutting metaflysch of the Valdez Group in the southern Valdez quadrangle. Data summarized by Goldfarb and others (1997) show that gold-bearing quartz veins in the Valdez Group commonly contain pyrite, arsenopyrite, carbonate minerals, chlorite, and white mica and formed from water-rich fluids with 5 to 15 mole percent CO2 and significant amounts of CH4, N2, and H2S. The vein-forming fluid salinities were less than 8 percent, vein formation temperatures ranged from 225 to 375 degrees centigrade, and emplacement depths varied from 3 to 10 kilometers. The vein-forming fluids were produced by metamorphic devolatilization reactions. Radiometric dating indicates that the veins formed from 57 to 49 Ma (Goldfarb and others, 1997, p. 171), when deep parts of the accreted Valdez Group flysch underwent high-grade metamorphism and partial melting (Hudson, 1994).
|Geologic map unit||(-146.734973003312, 61.2065760014028)|
|Mineral deposit model||Low-sulfide Au-quartz veins (Cox and Singer, 1986; model 36a)|
|Mineral deposit model number||36a|
|Age of mineralization||Radiometric dating indicates that the gold-bearing quartz veins in the Valdez Group formed from 57 to 49 Ma (Goldfarb and others, 1997, p. 171), when deep parts of the accreted Valdez Group flysch underwent high-grade metamorphism and partial melting (Hudson, 1994).|
|Alteration of deposit||Country rocks to gold-bearing quartz veins in Valdez Group metaflysch can be variably silicified, carbonitized, and sericitized (Goldfarb and others, 1997).|
|Workings or exploration||The veins were developed by three adits and more than 2,000 feet of underground workings (Johnson, 1915; Cobb, 1979 [OFR 79-1241]; Jansons and others, 1984).|
|Indication of production||Yes; small|
|Production notes||A mill was installed on site, and the total reported production between 1911 and 1922, was 1,997 ounces of gold and 187 ounces of silver, from 1,560 tons of ore (Hoekzema and others, 1986). The average grade indicated by this production is about 1.3 ounces of gold per ton.|
Cobb, E.H., 1979, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Valdez quadrangle, Alaska: U.S. Geological Survey Open-File Report 79-1241, 167 p.
Cobb, E.H., and Matson, N.A., Jr., 1972, Metallic mineral resources map of the Valdez quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-438, 1 sheet, scale 1:250,000.
Goldfarb, R.J., Miller, L.D., Leach, D.L., and Snee, L.W, 1997, Gold deposits in metamorphic rocks in Alaska, in Goldfarb, R.J., and Miller, L.D., eds., Mineral Deposits of Alaska: Economic Geology Monograph 9, p. 151-190.
Hoekzema, R.B., Fechner, S.A., and Kurtak, J.M., 1986, Evaluation of selected lode gold deposits in the Chugach National Forest, Alaska: U.S. Bureau of Mines Information Circular 9113, 62 p.
Hudson, T.L., 1994, Crustal melting events in Alaska, in Plafker, G., and Berg, H. C., eds., The Geology of Alaska: Geological Society of America, DNAG, The Geology of North America, Vol. G-1, p. 657-670.
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.
Johnson, B.L., 1915, Mining on Prince William Sound: U.S. Geological Survey Bulletin 622-E, p. 131-139.
Pickthorn, W.J., 1982, Stable isotope and fluid inclusion study of the Port Valdez district, southern Alaska: Los Angeles, University of California at Los Angeles, M.S. thesis, 66 p.
Winkler, G.R., Miller, R.J., MacKevett, E.M., Jr., and Holloway, C.D., 1981, Map and summary table describing mineral deposits in the Valdez quadrangle, southern Alaska: U.S. Geological Survey Open-File Report 80-892-B, 2 sheets, scale l:250,000.
|Reporters||Travis L. Hudson|
|Last report date||12/14/2001|