Unnamed (on ridge between Chistochina Glacier and glacier near the head of West Fork Chistochina River)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Cu
Other commodities Ag
Ore minerals azurite; malachite

Geographic location

Quadrangle map, 1:250,000-scale MH
Quadrangle map, 1:63,360-scale A-2
Latitude 63.1803
Longitude -144.9487
Nearby scientific data Find additional scientific data near this location
Location and accuracy The occurrence is on the ridge between the Chistochina River and the glacier at the head of the West Fork Chistochina River, about 3 miles north of their confluence; it is at an elevation of about 5,400 feet. The occurrence is about 0.1 mile southwest of the center of section 18, T. 20 S., R. 15 E., Fairbanks Meridian. The occurrence corresponds to locality 10 on figure 2 of Rose (1967) and locality 130 in table 2 of Nokleberg and others (1991); the location is probably accurate within 1,000 feet.

Geologic setting

Geologic description

The rocks in vicinity of this occurrence are dacite and andesite of the Chisna Formation (Rose, 1967). The rocks possibly belong to the Tetelna Volcanics or Slana Spur Formation of Richter and Dutro (1975). A north-trending dike of quartz monzonite that can be traced for about 2 miles cuts the volcanic rocks.
Float fragments of dacite and andesite are stained with azurite and malachite (Rose, 1967; Nokleberg and others, 1991). A grab sample from the locality contained 5 parts per million silver. Two nearby occurrences, MH280 and MH281, are also in volcanic wall rocks near the quartz monzonite dike.
Geologic map unit (-144.950923965079, 63.1798999670419)
Age of mineralization Possibly related to the Pennsylvanian to Permian volcanic rocks or related to the Mesozoic quartz monzonite.

Production and reserves

Workings or exploration Only limited surface sampling and geologic mapping.
Indication of production None