Radovan

Prospect, Inactive

Alternative names

Low Contact

Commodities and mineralogy

Main commodities Cu
Other commodities Ag; As; Sb
Ore minerals chalcocite; chalcopyrite; marcasite; pyrite; orpiment; realgar; stibnite
Gangue minerals calcite; chalcedony; dolomite; epidote; quartz

Geographic location

Quadrangle map, 1:250,000-scale MC
Quadrangle map, 1:63,360-scale B-4
Latitude 61.4016
Longitude -142.3716
Nearby scientific data Find additional scientific data near this location
Location and accuracy This prospect in the cirque at the head of Radovan Gulch (MacKevett and Smith, 1972). It is at an elevation of about 5,200 feet, 3,000 feet southeast of elevation 7850 and 1,500 feet south of the center of section 28, T. 5 S., R. 17 E. of the Copper River Meridian. This is locality 65 of MacKevett (1976) and it is accurately located. Cobb and MacKevett (1980) included the prospect under the name 'Radovan'.

Geologic setting

Geologic description

The deposit at this prospect consists of a brecciated fault zone that contains sporadically distributed chalcocite, chalcopyrite, pyrite, and marcasite (Miller, 1946). Realgar, orpiment, and stibnite are also reported to be localized in the fault zone but their relation to the copper mineralization is not clear (Sainsbury, 1951). The fault zone strikes N 25 E, dips 70-75 SE and has a vertical displacement of 1000 feet; it is the same fault zone as the one at the Radovan Greenstone prospect to the north (MC157). The fault is a 100-foot-wide, shattered zone that includes limonite-stained altered zones, gouge, and broken and recemented colloform bands of calcite, dolomite, and chalcedony. Quartz and epidote are also gangue minerals in the fault zone. In one outcrop, veins of chalcocite, 1- to 6-inches wide, occur over a surface area of 50 square feet (Sainsbury, 1951). The fault zone displaces the contact between the Triassic Nikolai Greenstone and the overlying Triassic Chitistone Limestone; the mineralization is along the part of the fault that places greenstone against limestone (MacKevett and Smith, 1972). The deposit has been explored by surface trenches and 2 short adits. Copper mineralization is common in Nikolai Greenstone and overlying Chitistone Limestone. It is thought to have accompanied regional deformation and low-grade metamorphism in the Late Jurassic to Early Cretaceous (MacKevett and others, 1997).
Geologic map unit (-142.373653276012, 61.4011773375617)
Mineral deposit model Basaltic Cu (Cox and Singer, 1986; model 23) and/or Kennecott-type copper deposit (after MacKevett and others, 1997)
Mineral deposit model number 23?
Age of mineralization Cretaceous? Copper mineralization is common in Nikolai Greenstone and overlying Chitistone Limestone. It is thought to have accompanied regional deformation and low-grade metamorphism in the Late Jurassic to Early Cretaceous (MacKevett and others, 1997).
Alteration of deposit Oxidation is evidenced by limonite staining. Silicification and epidotization are locally present in the fault zone.

Production and reserves

Workings or exploration The deposit has been explored by surface trenches and 2 short adits.
Indication of production Yes; small

Additional comments

The locality is in the Wrangell-Saint Elias National Park and Preserve.

References