Unnamed Prospect (ARDF - SO145; in headwaters of Penny Creek), Nome Mining District, Nome Census Area, Alaska, USAi

Regional Level Types
Unnamed Prospect (ARDF - SO145; in headwaters of Penny Creek)	- not defined -
Nome Mining District	Mining District
Nome Census Area	Census Area
Alaska	State
USA	Country

Location: This occurrence is on the low ridge, at about 650 feet elevation, between the headwaters of Penny Creek (SO018) and Minnesota Creek. It is locality 11 of Asher (1969, DGGS R33).
Geology: This occurrence is one of several in the area where sparse disseminated copper minerals, mainly malachite, occur in silica-rich rocks along the contact between marble and schist. Grab samples of these rocks contain 0.13 to 0.78 percent Cu but generally only traces of gold. However, samples from this specific locality contained 0.02 to 0.08 ounces Au per ton and 0.02 to 0.04 ounces Ag per ton (Asher, 1969, DGGS R33). This type of copper occurrence is present at several localities in the western Solomon quadrangle (Gamble, 1988) and has similarities to several in the Kougarok area of the northeastern Teller quadrangle. In the Teller quadrangle, the Ward mine (TE071) is an example of this type of copper mineral occurrence. The Ward mine has been described as a zone of silicification in marble above a thrust contact with underlying metapelitic schist (Sainsbury and others, 1969; Sainsbury, 1975, p. 90-94). The silica-rich rocks have been metamorphosed and commonly have a laminar fabric. Copper-bearing minerals, mostly malachite but also including azurite and in places chalcopyrite and possibly bornite, are disseminated in the silica-rich rocks. The minor sulfides tend to be along faint laminae and joints (Sainsbury and others, 1969, p. 22). Malachite and azurite also occur in small veins and veinlets in the silica-rich rocks. The summary characterization of this type of Seward Peninsula mineral deposit by Sainsbury (1975, p. 90-94) contains inconsistencies with some descriptions of these deposits. Their origin is uncertain and other possibilities should be considered. One possiblity is that the silica-rich rocks are quartzites and that there is a stratigraphic control to the Ward deposit and similar occurrences elsewhere on Seward Peininsula. Quarzite at the base of the regional carbonate assemblage is recognized elsewhere in the Kougarok Mountain area (Puchner, 1986, p. 1777). Bedrock in the area of this occurrence is part of a lower Paleozoic metasedimentary assemblage (Till and others, 1986).
Workings: No exploration or development work is reported for this occurrence.
Age: Unknown; if stratigraphic controls are important then it is probably Paleozoic in age.
Alteration: Silicification (?) and oxidation; the development of silica-rich rocks at or near the the base of Paleozoic marble overlying characterizes this type of copper occurrence.

Commodities (Major) - Au, Cu
Development Status: None
Deposit Model: Copper-bearing mineralization in silica-rich zones at or near base of marble.

Other Databases

Link to USGS - Alaska:	SO145

Other Regions, Features and Areas containing this locality

References