Unnamed (on peak 5480 southeast of Clearwater Creek)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Ag; Pb; Zn
Other commodities Cu; Mo
Ore minerals galena; malachite; sphalerite; pyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale MH
Quadrangle map, 1:63,360-scale A-6
Latitude 63.2093
Longitude -146.8935
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is near the top of peak 5480 near the center of section 1, T. 20 S., R. 4 E., Fairbanks Meridian. It corresponds to locality 8 in table 2 of Nokleberg and others (1991) and is about the same as a site sampled by Anaconda Minerals Company (Ellis, 1980). A probably related site is locality 20 of Clautice and others (1989), which is about one-quarter mile southeast of peak 5480 on the ridge crest.

Geologic setting

Geologic description

The rock near the occurrence is muscovite schist, probably metarhyolite. The rocks are cut by low-angle (thrust) faults (Nokleberg and others, 1991). The deposit is a polymetallic vein rich in lead. Sample 82NK017C collected by the U.S. Geological Survey assayed 9.4 percent lead, 0.97 percent zinc, 0.27 percent copper, 47 parts per million (ppm) silver, and 15 ppm molybdenum (Nokleberg and others, 1991). A sample collected by Anaconda Minerals Company assayed 1.17 percent lead, 0.1 percent zinc, 0.305 percent copper, and 86 ppm molybdenum (Ellis, 1980). Similar mineralization was reported at a nearby site by Clautice and others (1989, their locality 20), where more than 1 percent lead, 0.52 percent zinc, and 0.26 percent copper occurred in a zone 2 to 3 inches wide in tuffaceous rock.
Geologic map unit (-146.895766626061, 63.2088585808066)
Mineral deposit model Polymetallic vein (Cox and Singer, 1986; model 22c).
Mineral deposit model number 22c
Age of mineralization The lead-rich vein deposit cuts muscovite schist of probable Paleozoic protolith age. The mineralization age is uncertain but possibly Cretaceous, related to widespread deformation that occurred at that time.

Production and reserves

Workings or exploration No extensive workings.
Indication of production None

References