Old Glory (upper workings)

Mine, Undetermined

Alternative names

American Eagle

Commodities and mineralogy

Main commodities Au
Ore minerals gold; pyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale KC
Quadrangle map, 1:63,360-scale C-6
Latitude 55.611
Longitude -131.999
Nearby scientific data Find additional scientific data near this location
Location and accuracy
The upper workings of the Old Glory mine and the adjacent American Eagle prospect are on the southwest slope of Gold Mountain at an elevation of 750-1000 feet, and about 1.35 miles northwest of the mouth of Falls Creek. The site is in section 24, T. 72 S., R. 88 E., of the Copper River Meridian. It corresponds to localities 251-1,2,3 and 253-1 in Maas and others (1995, fig. 46). The location is accurate within 0.1 mile.
Also see Additional comments.

Geologic setting

Geologic description

The country rocks near this site are andesitic and basaltic metavolcanic rocks that gradationally intertongue with subordinate flyschlike metasedimentary rocks (Berg and others, 1988, p. 17-19). The strata were regionally metamorphosed to greenschist-grade phyllite and semischist in Late Cretaceous time (Brew, 1996, p. 27). Their premetamorphic age is uncertain. Berg and others (1988, p. 17) state that they closely resemble Upper Jurassic to mid-Cretaceous marine flysch and volcanic rocks nearby on Gravina Island.
The following description is based mainly on examinations of the upper Old Glory and American Eagle deposits by Maas and others (1995). The deposits at the Old Glory (upper workings) and American Eagle properties consist of quartz fissure veins and stringer lodes in massive to schistose metavolcanic rocks (greenstone) and interbedded chlorite schist (Maas and others, 1995, p. 183-184 and fig. 46). The veins contain pyrite and free gold and the schistose wallrocks adjacent to some of the veins are bleached and pyritized. The upper Old Glory workings date to the early 1900s and consist of 3 adits of unknown length; the American Eagle deposit was explored at that time by a 336-foot adit (Maas and others, table 26). Brooks (1902, p. 57) reported that a two-stamp mill was under construction at the time of his visit. Gold production, if any, from the upper Old Glory probably is included in the cumulative production figures for the Old Glory mine given by Maas and others (1995, table 26) (see KC033).
Maas and others (table 25) report the following average metal contents in their samples from the upper Old Glory lode: 4.32 ppm Au, 0.35 ppm Ag, 128 ppm Cu, 120 ppm Pb, and 67 ppm Zn. Samples from the American Eagle lode contain: 1.86 ppm Au, 0.12 ppm Ag, 157 ppm Cu, 11.2 ppm, Pb, and 71 ppm Zn.
Fluid inclusion studies of quartz vein material from several of the Helm Bay lodes suggest that the veins formed at temperatures and pressures consistent with conditions during the Late Cretaceous greenschist-grade regional metamorphism (Maas and others, 1995, p. 184).
Geologic map unit (-132.000683183926, 55.6106369831163)
Mineral deposit model Low-sulfide gold-quartz veins (Cox and Singer, 1986; model 36a)
Mineral deposit model number 36a
Age of mineralization Late Cretaceous.
Alteration of deposit The wallrocks adjacent to some of the veins are bleached and pyritic.

Production and reserves

Workings or exploration
The upper Old Glory workings date to the early 1900s and consist of three adits of unknown length; the American Eagle deposit was explored at that time by a 336-foot adit (Maas and others, table 26). Brooks (1902, p. 57) reported that a two-stamp mill was under construction at the time of his visit.
Maas and others (table 25) report the following average metal contents in their samples from the upper Old Glory lode: 4.32 ppm Au, 0.35 ppm Ag, 128 ppm Cu, 120 ppm Pb, and 67 ppm Zn. Samples from the American Eagle lode contain: 1.86 ppm Au, 0.12 ppm Ag, 157 ppm Cu, 11.2 ppm, Pb, and 71 ppm Zn.
Indication of production Yes; small
Production notes Gold production, if any, from the upper Old Glory probably is included in the cumulative production figures for the Old Glory mine given by Maas and others (1995, table 26) (see KC033).

Additional comments

This description is based mainly on examinations of the upper Old Glory and American Eagle deposits by the U.S. Bureau of Mines in the early 1990s (Maas and others, 1995). Earlier reports include those by Brooks (1902), Wright and Wright (1908), and Smith (1914). Their reports, in turn, were summarized by Elliott and others (1978) and Cobb and Elliott (1980).

References

MRDS Number A012309

References

Reporters H.C. Berg, USGS
Last report date 6/30/1999