Copper King

Prospect, Probably inactive

Commodities and mineralogy

Main commodities Cu; Pb
Other commodities Ag; Au
Ore minerals azurite; bornite; chalcopyrite; galena; malachite; pyrite
Gangue minerals mica; quartz

Geographic location

Quadrangle map, 1:250,000-scale NM
Quadrangle map, 1:63,360-scale D-1
Latitude 64.8802
Longitude -165.2131
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Copper King prospect is on the northwest flank of hill 1610, which lies between Copper Creek and Dickens Creek. The prospect is at an elevation of about 1,100 feet, 0.75 mile south of the Nome-Taylor road near the divide between the Nome River and Salmon Lake drainages. The prospect is located within about 500 feet. It is locality 6 of Hummel (1962 [MF 248]) and included with other nearby prospects in locality 16 of Cobb (1972 [MF-463], 1978 [OFR 78-93]).

Geologic setting

Geologic description

Hummel (1962 [MF 248]) noted the presence of copper and lead minerals here. On the basis of descriptions of copper mineralization in the general area (Smith, 1908; Cathcart, 1922), the mineralization is likely to include azurite, malachite, bornite, chalcopyrite, pyrite, and possibly galena in silica-rich rocks near a marble-schist contact. Early workers noted that the mineralization was stratabound but interpreted it to be in silicified zones and to have a replacement origin.
Picked samples (probably from the Copper Mountain prospect, NM054, 0.6 mile to the south) contained 15 percent copper, 20 percent lead, and 'rather high silver and low gold content' (Smith, 1908, p. 240-242). This prospect appears to have similarities to several other copper-bearing deposits in the eastern Teller quadrangle (for example, the Ward mine, Hudson, 1998, TE071) and in the western Solomon quadrangle (for example, the Wheeler mine, Hudson, 1999, SO172).
The Copper King prospect occurs in graphitic calc-mica schist with interlayered marble; the schist includes concordant bodies of granitic orthogneiss; one of the orthogneiss bodies occurs below the Copper King prospect (Hummel, 1962, MF-248; Thurston, 1985, figure 3A). Cathcart (1922, p. 219) described the orthogneiss as mainly fine grained, but with local porphyritic facies. An orthogneiss body 4.5 miles to the northeast has been determined to have a 678 Ma protolith age (Amato and Wright, 1998).
The metamorphic rocks are part of the Nome Group and derived from Precambrian to early Paleozoic protoliths (Till and Dumoulin, 1994). The Nome Group underwent regional blueschist facies metamorphism in the Late Jurassic or Early Cretaceous (Sainsbury, Coleman, and Kachadoorian, 1970; Forbes and others, 1984; Thurston, 1985; Armstrong and others, 1986; Hannula and McWilliams, 1995). The blueschist facies rocks were recrystallized to greenschist facies or higher metamorphic grades in conjunction with regional extension, crustal melting, and magmatism in the mid-Cretaceous (Hudson and Arth, 1983; Miller and Hudson, 1991; Miller and others, 1992; Dumitru and others, 1995; Hannula and others, 1995; Hudson, 1994; Amato and others, 1994; Amato and Wright, 1997, 1998). Lode gold mineralization on Seward Peninsula is mostly related to the higher temperature metamorphism in the mid-Cretaceous (Apodoca, 1994; Ford, 1993 [thesis]; Ford and Snee, 1996; Goldfarb and others, 1997). The age of nearly stratabound copper occurrences is more enigmatic, with a range of ages from that of the protolith through the late Proterozoic emplacement of some orthogneiss to the mid-Cretaceous.
Geologic map unit (-165.215726311815, 64.8794436018733)
Mineral deposit model Carbonate-hosted, sulfide-bearing silica-rich rock.
Age of mineralization Late Proterozoic, early Paleozoic, or mid-Cretaceous.
Alteration of deposit Bleaching, development of silica-rich rock, introduction of white mica, and oxidation.

Production and reserves

Workings or exploration There is a short adit and shallow shaft on the property. The earliest workings were before 1908 (Smith, 1908). There has been little recent work.
Indication of production None

References

MRDS Number A012793

References

Apodoca, L.E., 1994, Genesis of lode gold deposits of the Rock Creek area, Nome mining district, Seward Peninsula, Alaska: Boulder, Colorado, University of Colorado, Ph.D. dissertation, 208 p.
Armstrong, R.L., Harakal, J.E., Forbes, R.B., Evans, B.W., and Thurston, S.P., 1986, Rb-Sr and K-Ar study of metamorphic rocks of the Seward Peninsula and southern Brooks Range, Alaska, in Evans, B.W., and Brown, E.H., eds., Blueschists and eclogites: Geological Society of America Memoir 164, p. 184-203.
Ford, R.C., 1993, Geology, geochemistry, and age of gold lodes at Bluff and Mt. Distin, Seward Peninsula, Alaska: Golden, Colorado School of Mines, Ph.D. dissertation, 302 p.
Ford, R.C., and Snee, L.W., 1996, 40Ar/39Ar thermochronology of white mica from the Nome district, Alaska--The first ages of lode sources to placer gold deposits in the Seward Peninsula: Economic Geology, v. 91, p. 213-220.
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.
Hannula, K.A., and McWilliams, M.O., 1995, Reconsideration of the age of blueschist facies metamorphism on the Seward Peninusla, Alaska, based on phengite 40Ar/39Ar results: Journal of Metamorphic Geology, v. 13, p. 125-139.
Hannula, K.A., Miller, E.L., Dumitru, T.A., Lee, Jeffrey, and Rubin, C.M., 1995, Structural and metamorphic relations in the southwest Seward Peninsula, Alaska; Crustal extension and the unroofing of blueschists: Geological Society of America Bulletin, v. 107, p. 536-553.
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.
Hudson, T.L., and Arth, J. G., 1983, Tin granites of Seward Peninsula, Alaska: Geological Society of America Bulletin, v. 94, p. 768-790.
Miller, E.L., Calvert, A.T., and Little, T.A., 1992, Strain-collapsed metamorphic isograds in a sillimanite gneiss dome, Seward Peninsula, Alaska: Geology, v. 20, p. 487-490.
Thurston, S.P., 1985, Structure, petrology, and metamorphic history of the Nome Group blueschist terrane, Salmon Lake area, Seward Peninsula, Alaska: Geological Society of America Bulletin, v. 96, p. 600-617.
Till, A.B., and Dumoulin, J.A, 1994, Geology of Seward Peninsula and St. Lawrence Island, in Plafker, G., and Berg, H.C., eds., The Geology of Alaska: Geological Society of America, DNAG, The Geology of North America, v. G-1, p. 141-152.
Reporters C.C. Hawley and Travis L. Hudson
Last report date 10/22/1999