Unnamed (ridge northeast of Spruce Peak)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Pb
Other commodities Ag; V; Zn
Ore minerals limonite; pyrite; vanadinite

Geographic location

Quadrangle map, 1:250,000-scale MM
Quadrangle map, 1:63,360-scale C-2
Latitude 63.5941
Longitude -150.6725
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is at an elevation of about 4300 feet on an unnamed ridge between upper Myrtle and upper Caribou creeks. It is about 1.1 miles northeast of Spruce Peak, in the SW1/4 SW1/4 section 21, T. 15 S., R. 16 W., Fairbanks Meridian. The location is accurate within 500 feet. The occurrence corresponds to number 58 of Bundtzen, Smith, and Tosdal (1976), 278 of Hawley and Associates (1978), and 66a of Bundtzen (1981).

Geologic setting

Geologic description

This occurrence is a stratabound gossan about 6 feet wide which can be traced northeasterly for at least 250 feet. It appears to be a continuation of, or parallel to, gossan exposed about 1500 feet to the northeast. The gossan is mainly in metafelsite of the lower Paleozoic Spruce Creek sequence; some also occurs nearby in graphitic schist (Hawley and Associates, 1978; Bundtzen, 1981, and Thornsberry, McKee, and Salisbury, 1984). The gossan marks half-inch-thick, stratiform bands in the metafelsite that contain up to 50 percent pyrite. Bundtzen, Smith, and Tosdal (1976) tentatively identified vanadinite, a secondary lead-vanadium mineral, in the bands. Gossan sampled by Hawley and Associates (1978) contained 1.7 ppm silver, 1050 ppm lead, and 240 ppm zinc.
Geologic map unit (-150.674784954311, 63.5936004390668)
Mineral deposit model Stratabound deposit in metafelsite.
Age of mineralization This stratabound, possibly syngenetic deposit may be lower Paleozoic, the protolith age of the Spruce Creek rocks.
Alteration of deposit Oxidation of iron and lead-vanadium(?) minerals.

Production and reserves

Workings or exploration There are no workings.
Indication of production None

Additional comments

This occurrence is in Denali National Park and Preserve.

References