Unnamed (near upper Niukluk River)

Prospect, Inactive

Commodities and mineralogy

Main commodities Ag; Cu; Pb; Zn
Ore minerals azurite; cerrusite; chalcopyrite; chrysocolla; galena; malachite
Gangue minerals limonite; pyrite; quartz

Geographic location

Quadrangle map, 1:250,000-scale BN
Quadrangle map, 1:63,360-scale A-4
Latitude 65.199
Longitude -163.866
Nearby scientific data Find additional scientific data near this location
Location and accuracy This prospect is on a ridge crest along the south side of an unnamed east headwater tributary of Niukluk River. It is about 2,000 feet south of the creek at an elevation of approximately 2,000 feet. It is 4,500 feet northwest of the skarn propect at BN110. This is locality 83 of Gamble (1988).

Geologic setting

Geologic description

Highly oxidized, locally brecciated pyrite-chalcopyrite-galena-bearing drusy comb-quartz veins in high grade metamorphic rocks are present here. Secondary minerals include limonite, azurite, cerussite, chrysocolla, and malachite. Grab samples contain up to greater than 2 % Pb, greater than 2% Cu, 8,200 ppm Zn, 300 ppm Ag, 460 ppm Sb, 1,000 ppm As, 190 ppm Cd, 70 ppm Sn, and 14 ppm Bi (Gamble, 1988). The mineralized rocks occur as float and on dumps of shallow prospect pits or short adits. This locality, and several others in this part of the Bendeleben A-4 quadrangle, are in high grade metamorphic rocks that are structurally above or peripheral to the crosscutting Pargon pluton. The Pargon pluton is mostly granodiorite and assumed to be Cretaceous in age (Till and others, 1986). It was emplaced at shallower depths than the more deep-seated Bendeleben pluton to the east. The metamorphic rocks peripheral to the western Pargon pluton are also intruded by small, felsic dikes and plugs including quartz porphyry and muscovite granite.
Geologic map unit (-163.868643174096, 65.1982753936467)
Mineral deposit model Polymetallic vein in high-grade metamorphic rocks (Cox and Singer, 1986; model 22c?).
Mineral deposit model number 22c?
Age of mineralization Cretaceous; this occurrence is probably related to emplacement of the Pargon pluton which is assumed to be Cretaceous in age.
Alteration of deposit Abundant secondary minerals are developed from the oxidation of sulfides.

Production and reserves

Workings or exploration Some shallow prospecting pits or short adit(s) are present here.
Indication of production None