Unnamed (Middle Fork Chandalar River)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Cu
Ore minerals chalcopyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale PS
Quadrangle map, 1:63,360-scale A-2
Latitude 68.18
Longitude -147.66
Nearby scientific data Find additional scientific data near this location
Location and accuracy Site is at an elevation of about 4,700 ft. approximately 1 1/4 miles east of Beaucoup Creek (SE1/4 sec. 35, T. 14 S., R. 19 E., of the Umiat Meridian). Location accurate within 1-mile radius.

Geologic setting

Geologic description

Occurrence described only as visible chalcopyrite and anomalous silver occurring in a quartz vein in Skajit Limestone beneath the contact with the Beaucoup Formation (Menzie and others, 1985). The area is mapped as the conglomerate member of Beaucoup formation (Menzie and others, 1985).
Geologic map unit (-147.662784007, 68.1796521058285)

Production and reserves

Indication of production None
Reserve estimates See Additional comments below.

Additional comments

May be same location described by Proffett (1977) as a 'steep North-South striking, cross cutting quartz vein with coarse chalcopyrite. The ore-bearing part is 1 to 3 ft. wide and may average 5 to 10 percent copper. The vein is more than 1,000 ft. in strike length.' Proffett (1977) also estimated that the occurrence 'may have potential for 10,000 - 100,000 ton' deposit. Cathrall and other (1977) reported 1 ppm Ag in a rock sample (sample number 75 RR 121).

References

MRDS Number A012515

References

Proffett, John, 1977, Progress Report--Atigun Project: Anaconda Company files, memo to D.A. Heatwole, July 31, 1977, 3 p. (Report held at the University of Wyoming, American Heritage Center, Anaconda Geologic Documents Collection)
Reporters J.M. Britton (Anchorage)
Last report date 11/17/1999