Unnamed (northwest of Purdy Mine)

Occurrence, Undetermined

Commodities and mineralogy

Main commodities Au
Ore minerals gold
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale EA
Quadrangle map, 1:63,360-scale A-2
Latitude 64.1226
Longitude -141.9597
Nearby scientific data Find additional scientific data near this location
Location and accuracy This unnamed occurrence is located at an elevation of about 2,650 feet on the ridgeline between Stonehouse Creek and Myers Fork; It is about 3.4 miles north-northwest of Chicken. The occurrence is in section 18, T. 27 N., R. 18 E., of the Copper River Meridian. The location is accurate.

Geologic setting

Geologic description

The rocks in the vicinity of this occurrence are predominantly granitic rocks of the Chicken pluton of Jurassic age (Werdon and others, 2001). Hornblende from the pluton gives a 40Ar/39Ar plateau age of 187.8 +/-0.9 Ma (Layer and others, 2002). The pluton is intruded by an undated, K-feldspar-porphyritic, biotite hornblende granite that is spatially associated with numerous aplite dikes (Werdon and others, 2001). The southern margin of this granite is brecciated and in high-angle fault contact with upper Paleozoic metasedimentary and metavolcanic rocks. The aplite dikes are commonly sericite-altered. A sample of a quartz-veined aplite dike with a weak iron-oxide stain contains 70 ppb gold, 1.4 ppm silver, 4 ppm bismuth, 74 ppm lead, and 50 ppm zinc (Szumigala and others, 2000).
Geologic map unit (-141.96198368046, 64.1222707638428)
Mineral deposit model Plutonic-related gold.
Age of mineralization Jurassic or younger.
Alteration of deposit Aplite dikes are commonly altered to sericite and are locally iron stained.

Production and reserves

Indication of production None

References