Nellie Group

Prospect, Inactive

Commodities and mineralogy

Main commodities Cu
Other commodities Zn
Ore minerals chalcopyrite; cubanite; pyrrhotite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale SR
Quadrangle map, 1:63,360-scale B-2
Latitude 60.3422
Longitude -147.7363
Nearby scientific data Find additional scientific data near this location
Location and accuracy The prospect is located 1.5 miles north-northwest of the head of Northeast Cove of Drier Bay and is at an elevation of about 650 feet. It is in the valley of a steep southwest-flowing creek. It is in the NW1/4 section 21, T. 3 N., R. 10 E., of the Seward Meridian. This is location 104 of Cobb and Richter (1972), location 133 of MacKevett and Holloway (1977), location 223 of Cobb and Tysdal (1980), and location S-58 of Jansons and others (1984). This location is accurate to within a quarter of a mile.

Geologic setting

Geologic description

The prospect consists of a N 25 E-trending shear zone that dips 75 SE, cutting greenstone country rock (Johnson, 1918 [B 662-C, p. 217-218]). Nelson and others (1985) have mapped the country rock as Orca Group of early Tertiary age. The workings on the prospect consist of five open cuts, a 6-foot-deep shaft, and a 36-foot adit. At the adit face, the shear zone is 9 feet wide and has a 2-inch-wide band of pyrrhotite and chalcopyrite near the footwall (Johnson, 1918 [B 662-C, p. 217-218]). This zone can be traced along strike for about three-quarters of a mile. At an elevation of 1,200 feet, a 6-foot-deep shaft exposes a 10-foot-wide shear zone containing chalcopyrite (Johnson, 1918 [B 662-C, p. 217-218]). Tysdal (1978 [MF-880-A]) summarizes the prospect as a limonite-stained sheared greenstone containing chalcopyrite, pyrrhotite, cubanite, and quartz. Samples collected from the prospect contained from 9 to 150 ppm copper and 25 to 150 ppm zinc (Kurtak and Jeske, 1986).
Geologic map unit (-147.738338140734, 60.3416271316838)
Mineral deposit model Besshi massive sulfide (Cox and Singer, 1986; model 24b)
Mineral deposit model number 24b
Age of mineralization Tertiary or younger; the mineralization is in rocks of the Orca Group of Tertiary age.
Alteration of deposit The shear zone is limonite-stained.

Production and reserves

Workings or exploration The workings on the prospect consisted of five open cuts, a 6-foot-deep shaft, and a 36-foot adit (Johnson, 1918 [B 662-C, p. 217-218]). The U.S. Bureau of Mines did not locate any of the reported workings when they visited the site in the early 1980s. They collected samples from what appeared to be the reported mineralized shear zone. Five random chip samples contained from 9 to 150 ppm copper and 25 to 150 ppm zinc (Kurtak and Jeske, 1986).
Indication of production None

Additional comments

Kurtak and Jeske (1986) reported that the working were collapsed and filled in.

References

References

Reporters Jeff A. Huber and Carol S. Huber (Anchorage)
Last report date 11/30/2001