Prospect, Inactive

Commodities and mineralogy

Main commodities Au
Ore minerals arsenopyrite; gold; pyrite
Gangue minerals ankerite; quartz

Geographic location

Quadrangle map, 1:250,000-scale NM
Quadrangle map, 1:63,360-scale C-1
Latitude 64.6785
Longitude -165.4772
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Lilly prospect is at an elevation of about 850 feet on the divide between the headwaters of Twin Mountains Creek and Bangor Creek. It is about one-quarter mile south of hill 992, in the NW1/4SE1/4 section 28, T. 9 S., R. 34 W., of the Kateel River Meridian. It was included in locality 36 of Cobb (1972 [MF 463], 1978 [OFR 78-93]). The prospect is locality 9 of Hummel (1962 [MF 247]) and it is located to within 500 feet.

Geologic setting

Geologic description

The Lilly prospect consists of pyrite and arsenopyrite in quartz veins and disseminated in silicified graphitic marble and schist near old prospect pits that probably are just east of the Rodine fault (Bundtzen and others, 1994). Soil samples in the area contain as much as 335 ppb gold and 1,650 ppm arsenic. In 1991, Kennecott Exploration Company cut two 2,000-foot-long backhoe trenches aligned north-south extending through the site (C.C. Hawley, Cindy Buxton, and Duane Olson, written communication, 1992). In addition to anomalous soil values near the old prospect, a vein zone that strikes east-northeast was discovered about 2,000 feet to the south. Soils over the vein zone contain more than 600 ppb gold and more than 4,000 ppm arsenic. The zone apparently contains local concentrations of free gold that were mined in a hill-slope placer deposit less than one-half mile southeast of the Lilly area (NM190). The Lilly lode was briefly described by Cathcart (1922, p. 252).
Geologic map unit (-165.479811935449, 64.6777344304884)
Mineral deposit model Low-sulfide Au-quartz veins (Cox and Singer, 1986; model 36a).
Mineral deposit model number 36a
Age of mineralization Mid-Cretaceous or younger; postdates mid-Cretaceous regional metamorphism.
Alteration of deposit Silicification; introduction of arsenopyrite into schist.

Production and reserves

Workings or exploration Exploration includes early 1900s prospect pits and more than 2,000 feet of trenches cut here in 1991 by Kennecott Exploration Company.
Indication of production None