Sunrise

Prospect, Inactive

Commodities and mineralogy

Main commodities Mn
Ore minerals manganite; psilomelane; pyrolusite; rhodochrosite; rhodonite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale TR
Quadrangle map, 1:63,360-scale A-6
Latitude 58.0748
Longitude -133.9308
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Sunrise manganese prospect is at an elevation of about 3,000 feet, about 2.3 miles northeast of Arthur Peak. It is near the northwest corner of section 11, T. 44 S., R. 70 E. of the Copper River Meridian. This is location T012 of Wells and others (1986). The location is accurate within 1/4 mile.

Geologic setting

Geologic description

The Sunrise manganese prospect consists of several outcrops of short manganese-bearing veins that are 1.0 to 3.5 feet wide, composed of about 70% rhodochrosite, 15% manganese dioxide (pyrolusite and/or manganite), 10% quartz, 5% rhodonite, and possibly some psilomelane (Wells and others, 1986). Several other parallel manganese-bearing veins 0.1 to 1.0 ft wide have been identified over a strike length of 6000 feet. The manganese-bearing veins are in a 200- to 300-foot section of phyllite that is overlain by schistose basalt and tuff. The veins are conformable to the phyllite which strikes N 50 W and dips 45-80 NE (Pittman, 1957). Pittman (1957) describes jasperoid at this prospect that may represent local silicification.
A channel sample 3.5 feet long contain 22.4% manganese; another over 1 foot long contain 31.6% manganese (Pittman, 1957). Roehm (1943) reported that assays of several samples of low-grade and high-grade veins vary from 10.76% to 38.45% manganese. A beneficiation test in 1957 by the U.S. Bureau of Mines produced a 40.6% manganese concentrate (Pittman, 1957). The beneficiation test failed to produce a marketable concentrate (Cobb, 1978 [OFR 78-698]). Development consists of a few shallow pits and trenches. The prospect was discovered by Henry 'Tiger' Olson in 1935 (Redman and others, 1985). There were active claims on the property from 1935 to 1979 (Wells and others, 1986).
Geologic map unit (-133.932542748701, 58.0744696348483)
Mineral deposit model Possible volcanogenic Mn (Cox and Singer, 1986; model 24c)
Mineral deposit model number 24c
Alteration of deposit Jasperoid may represent local silicification (Pittman, 1957).

Production and reserves

Workings or exploration Development consists a few shallow pits and trenches. The prospect was discovered by Henry 'Tiger' Olson in 1935 (Redman and others, 1985). There were active claims on the property from 1935 to 1979 (Wells and others, 1985).
Indication of production None

References