Prospect, Inactive

Commodities and mineralogy

Main commodities Pb; Sb
Other commodities Cu
Ore minerals galena; malachite; stibnite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale DN
Quadrangle map, 1:63,360-scale C-2
Latitude 63.5756
Longitude -150.7217
Nearby scientific data Find additional scientific data near this location
Location and accuracy
The Mystery prospect (Cobb, 1980 [OFR 80-363]) is at an elevation of about 3950 feet on the ridge at the head of Spruce Creek. It is in the NW1/4 NE1/4 section 31, T. 15 S., R. 16 W., Fairbanks Meridian. The location probably is accurate within 1/2 mile.
There are several prospects at the head of Spruce Creek, and the exact site of the Mystery prospect is uncertain. The location for this record is based in part on the Alaska State Kardex file (KX 66-23: Heiner and Porter, 1972; Hawley and Associates, 1978). The Mystery prospect is included with other nearby prospects, including the Lena and Silver Wires (DN061), in location 22 of Cobb (1972 [MF 366]).

Geologic setting

Geologic description

The country rocks in the area of the Mystery prospect are graphitic phyllite and marble of the lower Paleozoic Spruce Creek sequence (Bundtzen, 1981; Thornsberry, McKee, and Salisbury, 1984, fig. K-2). The deposit consists of a 2.5-foot-thick quartz vein that contains galena, stibnite, and a secondary copper mineral, probably malachite (Davis, 1923, p. 132). No other information about the deposit has been published and it has not been found, with certainty, by any of the more recent surveys of the area.
Geologic map unit (, )
Mineral deposit model Polymetallic vein? (Cox and Singer, 1986; model 22c?).
Mineral deposit model number 22c?
Age of mineralization The deposit is assumed to be Eocene (see record DN091).
Alteration of deposit Oxidation of copper mineral.

Production and reserves

Workings or exploration Probably explored by shallow pits, since sloughed. The prospect was last active in 1922 (Heiner and Porter, 1972).
Indication of production None

Additional comments

The prospect is in Denali National Park and Preserve.