Sulphide

Occurrence, Inactive

Commodities and mineralogy

Main commodities Au
Other commodities Ag; Pb
Ore minerals arsenopyrite; gold; pyrite; scorodite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale MM
Quadrangle map, 1:63,360-scale C-2
Latitude 63.5375
Longitude -150.9311
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Sulphide occurrence (Cobb, 1980 [OFR 80-363]) is in the canyon of Eureka Creek at an elevation of about 2100 feet. It is on a patented claim, in the SW1/4 SW1/4 section 7, T. 16 S., R. 17 W., Fairbanks Meridian. The location is accurate within 500 feet. The occurrence is number 22 of Hawley and Associates (1978), 33 of Bundtzen (1981), and 38 of Thornsberry, McKee, and Salisbury (1984).

Geologic setting

Geologic description

A quartz vein at the Sulphide claim cuts Birch Creek schist. Davis (1923) described an 8-foot-thick quartz vein in the discovery cut near the center of the claim that contains pyrite; panned samples of the vein contained gold. Bundtzen (1981) reported that the vein, which he traced for about 150 feet, contains arsenopyrite, boulangerite, and pyrite. The arsenopyrite is partly oxidized to scorodite. Hawley and Associates (1978, nos. 137-38, table 4.1-A(1)) collected rock samples near the prospect that assayed as much as 20 ppm silver and 1.9 ppm gold.
Geologic map unit (-150.933385540408, 63.5369940372599)
Mineral deposit model Low-sulfide gold-quartz vein (Cox and Singer, 1986; model 36a).
Mineral deposit model number 36a
Age of mineralization The deposit is assumed to be Eocene (see record MM091).
Alteration of deposit Partial oxidation of arsenopyrite to scorodite.

Production and reserves

Workings or exploration Sloughed pits date at least as far back as 1922.
Indication of production None

Additional comments

The prospect is in Denali National Park and Preserve; it has been inactive for many decades.

References