Prospect, Inactive

Commodities and mineralogy

Main commodities Ag
Other commodities Pb; Zn
Ore minerals anglesite; arsenopyrite; galena; pyrite; sphalerite
Gangue minerals 'carbonates; ' quartz

Geographic location

Quadrangle map, 1:250,000-scale DN
Quadrangle map, 1:63,360-scale C-2
Latitude 63.5526
Longitude -150.8726
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Waterloo prospect, on a patented claim, is at an elevation of about 3450 feet on the ridge at the head of the unnamed east fork of Twentytwo Gulch. It is at the approximate center of the north sideline of the claim, which abuts the east endline of the Chloride claim (DN099). The location is near the boundary between the SE1/4 and NE1/4 of the SE1/4 section 5, T. 16 S., R. 17 W., Fairbanks Meridian. It is accurate within 500 feet. The site corresponds to number 37 of Bundtzen, Smith, and Tosdal (1976), 44 of Bundtzen (1981), 34 of Hawley and Associates (1978), and 56 of Thornsberry, McKee, and Salisbury (1984).

Geologic setting

Geologic description

The Waterloo claim area is underlain by chloritic phyllite, metafelsite, and graphitic schist of the lower Paleozoic Spruce Peak sequence (Bundtzen, 1981). The area is cut by steep, NE-striking faults (Thornsberry, McKee, and Salisbury, 1984, v. 2).
The deposit consists of mineralized quartz-carbonate veins. Bundtzen (1981) collected a sample containing massive galena, partly oxidized to anglesite, and small amounts of sphalerite. The sample assayed 52 percent lead and 79.1 ounces of silver per ton. In 1983, the U.S. Bureau of Mines examined several shallow pits that exposed rock containing disseminated pyrite, arsenopyrite, and sparse base-metal sulfides (Thornsberry, McKee, and Salisbury, 1984, v. 2, occurrence 56). Hawley and Associates (1978; fig. 4.1-1(A), nos. 125-128) collected rock samples on and immediately north of the claim. These samples assayed up to 0.35 percent lead, 0. 27 percent zinc, 18 ppm silver, and 1.2 ppm gold, values similar to those obtained in samples collected by the Bureau in 1983 . Hawley and Associates interpret these values to indicate widespread, low-grade mineralization in the area of the claim.
Geologic map unit (, )
Mineral deposit model Polymetallic veins (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 Local oxidation of lead mineral.

Production and reserves

Workings or exploration The prospect was explored by shallow trenches and pits probably dating to the 1940s or earlier.
Indication of production None

Additional comments

The prospect is in Denali National Park and Preserve.