|Quadrangle map, 1:250,000-scale||MD|
|Quadrangle map, 1:63,360-scale||A-4|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The Ruby Creek (Strand) placer gold deposit is the lower portion of the Ruby Creek placer (see Ruby Creek; MD068). It is located below the confluence of Crystal Gulch at an elevation of 750 feet in Section 14, T. 26 S., R. 21 E., of the Kateel River Meridian. Location is known to within 250 feet (76 m).|
Geologic descriptionNo data on size or grade of the Ruby Creek (Strand) deposit has been found in published sources. Ilmenite and magnetite were abundant in concentrates. The Strand part of the Ruby Creek placer is a mature, third order stream with an average gradient of about 150 feet/ mile. The upper end above Crystal Gulch is a second order stream with a higher gradient. In 1929, fineness was estimated to be 807 gold and 107 silver (Mertie, 1936). Age is Quaternary, based on inference with similar deposits in area (Bundtzen and others, 1997).
|Geologic map unit||(-154.798325796634, 63.2353919779412)|
|Mineral deposit model||Placer Au-PGE (Cox and Singer, 1986; model 39c).|
|Mineral deposit model number||39c|
|Age of mineralization||Quaternary, based on inference with similar deposits in area (Bundtzen and others, 1997).|
|Workings or exploration||Both underground drifting and open cut methods were used prior to 1933 (Mertie, 1936).|
|Indication of production||Yes; small|
|Production notes||Ruby Creek was the first to be mined in the Nixon Fork area (1917). From 1917 to 1942, Ruby Creek produced at least 1,522 ounces (47 kg) gold and unknown amounts of silver. Production continued intermittently until about 1961, but the latter year's production levels were believed to be modest.|
Additional commentsSee also Hidden Creek (MD066), Upper Ruby Creek (MD068), Birch Gulch (MD073), and Holmes Gulch (MD072).
Cobb, E.H., 1978, Summary of references to mineral occurrences in the Beaver, Bettles, and Medfra quadrangles: U.S. Geological Survey Open File Report 78-94, 54 pages.
Herreid, G.H., 1966, Geology and geochemistry of the Nixon Fork area, Medfra quadrangle, Alaska: Alaska Division of Mines and Minerals Geologic Report 22, 34 p., 1 sheet, scale 1:40,000.
Martin, G.C., 1922, Gold lodes in the upper Kuskokwim region: U.S. Geological Survey Bulletin 722-E, p. 149-161.
|Reporters||Bundtzen, T.K. (Pacific Rim Geological Consulting)|
|Last report date||6/7/1998|