American Creek

Mines, Active?

Alternative names

Teddys Fork
Discovery Fork
Alder Gulch

Commodities and mineralogy

Main commodities Au
Other commodities Pt; REE
Ore minerals gold; monazite; platinum

Geographic location

Quadrangle map, 1:250,000-scale EA
Quadrangle map, 1:63,360-scale C-1
Latitude 64.6794
Longitude -141.3246
Nearby scientific data Find additional scientific data near this location
Location and accuracy American Creek is a 20-mile-long tributary of Mission Creek, whose mouth is near Eagle. American Creek has two major branches, Teddys Fork and Discovery Fork, but most reports refer to Teddy's Fork simply as American Creek. The coordinates are where most placer mining occurred, near the junction of Discovery Fork, Teddys Fork, and American Creek, in section 4, T. 3 S., R. 32 E., of the Fairbanks Meridian. The location is accurate. This record combines the references to Teddys Fork, Discovery Fork, and Alder Gulch (a small tributary of Teddys Fork that is not labeled on the U.S. Geological Survey topographic map of the Eagle C-1 quadrangle (1956; revised in 1973). American Creek is localities 35, 37 and 38 of Cobb (1972 [MF-393]), locality 2 of Eberlein and others (1977), and localities 18, 19, and 21 of Burleigh and Lear (1994).

Geologic setting

Geologic description

The rocks along upper American Creek are Paleozoic quartz-mica schist, greenschist, marble, and greenstone and Paleozoic or Mesozoic serpentinite (Foster, 1976). Bedrock on lower American Creek is Paleozoic or Mesozoic serpentinite, Cretaceous to Tertiary nonmarine sedimentary rocks, and Paleozoic greenstone, quartzite, and argillite. Extensive Quaternary terrace deposits occur near the mouth of the creek.
Most placer gold mining occurred near the junction of Discovery Fork with American Creek, an area commonly referred to as the Forks. Placer mining also occurred on lower American Creek within 5 miles of the mouth, but little or no work was done in the intervening stretch. Placers of the lower valley are interpreted to have a secondary source in the Cretaceous to Tertiary clastic sedimentary rocks (Mertie, 1938). Gravel in the lower valley is 15 to 40 feet thick, and coarse gold was recovered (Powers, 1935).
Most placer gold from American Creek was recovered near the Forks. The average depth of overburden in this area was about 14 feet. The valley is about 30 yards wide, and gravels averaged about 65 cents to the square foot of bedrock in 1936 (gold at $35.00 per ounce) (Mertie, 1938). One cut just below the Forks exposed 12 feet of gravel. Gold was fairly coarse and included several large nuggets. Fineness of the gold at this site was not determined, but it sold for about $28 per ounce (gold at $35 an ounce) (Mertie, 1938). There is also a poorly defined bench about 1 mile north of the Forks, about 15 feet above the creek. The gravel here is about 5 feet thick and consists of 3 feet of loose gravel and 2 feet of clay-rich gravel. Gold is found throughout the lower half of this gravel, but the best pay is next to bedrock and within the upper 2 feet of bedrock (Prindle, 1905). Much of the gold is coarse.
Placer gold has also been recovered on Discovery Fork and its tributary Star Gulch. The depth to bedrock on the lower part of Discovery Fork is about 7 to 9 feet; the gold lies on and in bedrock. A 19-ounce nugget was recovered from Discovery Fork, but most of the gold was in smaller particles (Mertie, 1938). Near the upper part of Discovery Fork, the gravel is 5 to 7 feet thick. The gold is coarser than that found downstream. Alder Gulch, a small tributary to American Creek, was mined out in a period of a few years. Rich pay was found in gravels from the mouth of Alder Gulch for about one-half mile upstream (Powers, 1935). Gold was also mined from Gravel Gulch in the early 1900s, but the location of this stream is uncertain (Foster and Keith, 1969).
The average fineness of 10 samples of placer gold from the upper part of American Creek and its tributaries was 865 parts of gold and 130 parts of silver per thousand (Mertie, 1942). Smith (1941 [B 910-C]) reported assays of 5 gold samples from American Creek. The fineness of one sample was 902, and the other four samples fell between 858 and 898 parts of gold per thousand. A nugget recovered in 1899 was valued at $192 (gold at $20.67 per ounce) (Brooks, 1900); it must have weighed about 11 ounces (Mertie, 1938). Placer concentrates contain abundant magnetite and barite, as well as some monazite. American Creek placers also contain platinum (Burleigh and Lear, 1994). Gold-bearing quartz veins in bedrock were reported near the head of American Creek (Spurr, 1898), but their location is unknown.
Placer gold on American Creek was discovered around 1891, and the stream has been mined intermittently since 1896. Placer gold was being actively mined in the late 1800s and early to middle 1900s, and American Creek and its tributary Discovery Fork were considered the most important gold-mining area in the vicinity of Eagle in 1905 (Prindle, 1905). The discovery claim on American Creek is located at the mouth of Discovery Fork and serves as the reference point for numbering claims on both forks (Mertie, 1938). In 1903 and 1904, miners used a hydraulic plant approximately 1 mile above the confluence of Discovery Fork, and an automatic water dump gate was installed on Discovery Fork (Brooks, 1905; Prindle, 1905). The 1912 season was considered profitable; the gravel over about 17,000 square feet of bedrock on American Creek and over about 11,000 square feet of bedrock on Discovery Fork were processed by shoveling dirt into sluice boxes (Ellsworth and Davenport, 1913). A nugget worth $80 was found at this time (gold at $20.67 per ounce) (Ellsworth and Davenport, 1913). American Creek, Discovery Fork, and Star Gulch were still being mined for placer gold in 1936 (Mertie, 1938), and mining continued until at least 1940. The lower end of Teddys Fork was being mined for placer gold in the late 1970s (Eberlein and others, 1977). Bulldozers, backhoes and sluice plants were used in later years to process the gravels. Small-scale placer mining on American Creek continues in the 1990s (Swainbank and others, 1993).
The first 15 years of mining on American Creek and its tributaries produced a considerable amount of gold (Powers, 1935). In 1896, one placer mine returned $27 per day per man (Spurr, 1898). Prindle (1905) estimated that as of 1905 about $20,000 worth of gold had been produced from Discovery Fork.
Geologic map unit (-141.326909718719, 64.6791103107456)
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 Placer gold on American Creek was discovered around 1891, and the stream has been mined intermittently since 1896. Placer gold was being actively mined in the late 1800s and early to middle 1900s, and American Creek and its tributary Discovery Fork were considered the most important gold-mining area in the vicinity of Eagle in 1905 (Prindle, 1905). The discovery claim on American Creek is located at the mouth of Discovery Fork and serves as the reference point for numbering claims on both forks (Mertie, 1938). In 1903 and 1904, miners used a hydraulic plant (Prindle, 1905) approximately one mile above the confluence of Discovery Fork, and an automatic water dump gate was installed on Discovery Fork (Brooks, 1905). The 1912 season was considered profitable; the gravel overlying about 17,000 square feet of bedrock on American Creek and over about 11,000 square feet of bedrock on Discovery Fork were processed by shoveling dirt into sluice boxes (gold at $20.67 per ounce) (Ellsworth and Davenport, 1913). American Creek, Discovery Fork, and Star Gulch were still being mined for placer gold in 1936 (Mertie, 1938), and mining continued until at least 1940. The lower end of Teddys Fork was being mined for placer gold in the late 1970s (Eberlein and others, 1977). Bulldozers, backhoes and sluice plants were used in later years to process the gravels. Small-scale placer mining on American Creek continues in the 1990s (Swainbank and others, 1993).
Indication of production Yes; medium
Production notes The first 15 years of mining on American Creek and its tributaries produced a considerable amount of gold (Powers, 1935). In 1896, one placer mine returned $27 per day per man (Spurr, 1898). Prindle (1905) estimated that as of 1905 about $20,000 worth of gold had been produced from Discovery Fork.

References

MRDS Number A015139

References

Brooks, A.H., 1900, A reconnaissance from Pyramid Harbor to Eagle City, Alaska, including a description of the copper deposits of the upper White and Tanana Rivers: U.S. Geological Survey Twenty-first Annual Report, p. 331-391, plate 2.
Reporters M.B. Werdon
Last report date 5/1/2002