Peggy Barbara

Prospect, Inactive

Alternative names

Ship Rock

Commodities and mineralogy

Main commodities Hg
Other commodities Sb
Ore minerals cinnabar; stibnite
Gangue minerals calcite

Geographic location

Quadrangle map, 1:250,000-scale MG
Quadrangle map, 1:63,360-scale A-4
Latitude 62.173
Longitude -154.865
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Peggy Barbara prospect is located on a limestone bluff adjacent to an east fork of the Cheeneetnuk River, about 1 mile (1.5 km) south of the White Mountain Mercury Mine airstrip in the NW1/4 sec. 18, T. 24 N., R. 30 W., of the Seward Meridian. The reporter visited the prospect in 1989 (Alaska Division of Geological and Geophysical Surveys station no. 89BT117).

Geologic setting

Geologic description

Mineralization at the Peggy Barbara prospect consists of small stringers and lenses of cinnabar and minor stibnite in black-gray limestone of the Early Devonian Cheeneetnuk Limestone (Gilbert, 1981; Blodgett and Gilbert, 1983). Cinnabar is found in limestone blocks at the base of and within a 15 meter high by 60 meter long cliff; limestone was first cut by calcite veins and later cinnabar-stibnite mineralization accompanied by more calcite veining.
The largest lens or pipe measures 10 cm by 30 cm in dimension with an unknown, steep rake into the limestone outcrop. One high grade sample contained 66.8% Hg (Sainsbury and MacKevett, 1965). Deposit geology is similar to that at the nearby Mary Margaret prospect (MG027) and the White Mountain Mercury mine (MG025).
Geologic map unit (-154.867283139524, 62.1723542942106)
Mineral deposit model Probably Hot Springs Mercury (Cox and Singer, 1986; model 27a).
Mineral deposit model number 27a
Alteration of deposit Dickite alteration.

Production and reserves

Workings or exploration Only surface sampling has been conducted on the property. One sample contained 66.8 percent mercury (Sainsbury and MacKevett, 1965).
Indication of production None

Additional comments

Mineralization may be related to the nearby Farewell-Denali strike slip fault system (Gilbert, 1981; Wilson and others, 1998).