Poorman Creek

Mine, Inactive

Commodities and mineralogy

Main commodities Au
Other commodities Barite; Sn
Ore minerals cassiterite; gold

Geographic location

Quadrangle map, 1:250,000-scale RB
Quadrangle map, 1:63,360-scale A-6
Latitude 64.07854
Longitude -155.65122
Nearby scientific data Find additional scientific data near this location
Location and accuracy Poorman Creek is a meandering stream that flows generally southwest through the Ruby A-6 quadrangle. Coordinates are given for the approximate midpoint of placer grounds that lie near the mouth of Solomon Creek, in section 26, T. 16 S., R. 16 E., Kateel River Meridian. This location corresponds with location 32 of Cobb (1972 [MF405]). Poorman Creek experienced heavier mining activity near the town of Poorman, in section 17, T. 16 S., R. 17 E. More information about this second area is given in the references for Duncan Creek (RB056), Little Pup (RB054), and Tenderfoot Creek (RB053). The location listed above is accurate.

Geologic setting

Geologic description

The bedrock on either side of Poorman Creek is Paleozoic phyllite and quartzite, but the stream flows within 2 miles of the Poorman fault, which juxtaposes Innoko terrane chert and slate against Ruby terrane phyllite, quartzite, marble, limestone, and Tertiary volcanic rocks (Puchner and others, 1998). Mertie (1936) reported the bedrock under Poorman Creek is phyllite and rhyolite porphyry.
Poorman Creek flows through an asymmetrical valley, where the south slope is steeper than the north. The upper valley is wide and open. Gold was discovered along Poorman Creek in 1912, and several holes were sunk to bedrock during that winter (Eakin, 1914 [B592-J]). Nearly the entire creek was staked during 1913 (Mertie and Harrington, 1916). Mining along Poorman Creek began in 1913 and continued nearly continuously until about 1976 (Eberlein and others, 1977).
There are no well-developed benches, but the pay streak below Tenderfoot Creek is on a 'bench' 600 to 1,000 feet north of the creek. Farther down the valley, the pay streak is south of the stream. Most mining took place on bench claims on the north bank of the creek (Mertie and Harrington, 1916). The main pay streak is about 2 1/2 miles long and as much as 1,000 feet wide (Eberlein and others, 1977).
Most of the pay is found in 3 to 6 feet of gravel near bedrock located 53 to 65 feet below the surface, although the depth to bedrock increases with distance from the creek (Eakin, 1914 [B592-J]; Mertie and Harrington, 1916). The gravel contains gold in fine, shot-like particles (Eakin, 1914 [B592-J]). Also found in the gravel are grains of pyrite, rounded and polished cassiterite pebbles, amorphous cassiterite (wood tin), barite pebbles, and a little magnetite (Mertie and Harrington, 1916). Assays of gold from several mines showed 835 to 853 parts gold per thousand and 154 to 159 parts silver per thousand (Mertie, 1936).
Production figures are not available for this creek, but Poorman Creek may have accounted for as much as 25 percent of the 390,000 ounces of gold reported recovered from the Ruby district from 1911 to 1960 (Cobb and Chapman, 1981). Although Poorman Creek was thought to have been mined out by 1977 (Eberlein and others, 1977), it also was mined between 1988 and 1995 (Green and others, 1989; Swainbank and others, 1991; Bundtzen and others, 1992; Bundtzen and others, 1996).
Geologic map unit (-155.653607009448, 64.0779350593237)
Mineral deposit model Placer Au (Cox and Singer, 1986; model 39a).
Mineral deposit model number 39a
Age of mineralization Quaternary.

Production and reserves

Workings or exploration Poorman Creek was prospected in 1912 and experienced nearly continuous mining from 1913 until at least 1995 (Eberlein and others, 1977; Green and others, 1989; Swainbank and others, 1991; Bundtzen and others, 1992; Bundtzen and others, 1996).
Indication of production Yes; small
Production notes Cobb and Chapman (1981) estimated that 25 percent of the total 390,000 ounces of placer gold production from the Ruby district between 1911 and 1960 was from Poorman Creek and its small tributaries.

Additional comments

Tributaries of Poorman Creek along which there are prospects or mines are Moose Creek (RB043), Beaver Creek (RB044), Eldorado Creek (RB046), Timber Creek (RB049), Solomon Creek (RB050), Nevada Creek (RB047), Tenderfoot Creek (RB053), Little Pup (RB054), and Duncan Creek (RB056). Additionally, Flat Creek (RB051), a tributary of Timber Creek, was also mined.

References

MRDS Number A010742; A015558; A015559

References

Reporters C.E. Cameron (Alaska Division of Geological and Geophysical Surveys)
Last report date 3/22/2000