|Quadrangle map, 1:250,000-scale||RB|
|Quadrangle map, 1:63,360-scale||B-6|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||Fifth of July Creek is a west-flowing tributary of Long Creek. The deposit is found in the lower portion of the creek, downstream from the winter trail marked on the Ruby B-6 quadrangle (USGS topographic map, 1952, minor revisions in 1972). The coordinates above correspond to location 14 of Cobb (1972 [MF-405]), and location 17 of Eberlein and others (1977), near the mouth of the creek, in section 8, T. 13 S., R. 17 E. of the Kateel River meridian. The location is accurate.|
The bedrock underlying Fifth of July Creek is Paleozoic phyllite, schist, metagraywacke, metachert, greenstone, and marble (Puchner and others, 1998).
Gold placer mines were operated around 1922 for a few years (Eberlein and others, 1977). The ground at the mouth was reported to be 70 to 80 feet deep, and at least 30 feet deep 0.3 miles above the mouth (Chapman and others, 1963). The gold production is unknown, but an incomplete recovery from gravel overlying 6,000 square feet of bedrock produced a washtub of cassiterite and iron-bearing concentrate (Chapman and others, 1963). Cassiterite, limonite, and black sands are common in this area. The gravel mined contained subangular to subround fragments of greenstone, schist, and quartz most of which measured less than 7 inches in diameters.Some of Fifth of July Creek's placer ground may be a bench of Long Creek which Fifth of July Creek intersects (Eberlein and others, 1977).
|Geologic map unit||(-155.558268235871, 64.377064053129)|
|Mineral deposit model||Placer Au (Cox and Singer, 1986; model 39a).|
|Mineral deposit model number||39a|
|Age of mineralization||Quaternary.|
|Workings or exploration||Fifth of July Creek was mined for a few years around 1922 (Eberlein and others, 1977).|
|Indication of production||Yes; small|
|Production notes||The gold production is unknown, but an incomplete recovery from gravel overlying 6,000 square feet of bedrock produced a washtub of cassiterite and iron-bearing concentrate (Chapman and others, 1963).|
Chapman, R.M., Coats, R.R., and Payne, T.G., 1963, Placer tin deposits in central Alaska: U.S. Geological Survey Open-File Report 239, 53 p.
Cobb, E.H., 1972, Metallic mineral resources map of the Ruby quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-405, 1 sheet, scale 1:250,000.
Cobb, E.H., and Chapman, R.M., 1981, Mineral occurrences (other than mineral fuels and construction materials) in the Kantishna River and Ruby quadrangles, Alaska: U.S. Geological Survey Open-File Report 81-170, 94 p.
Eberlein, G.D., Chapman, R.M., Foster, H.L., and Gassaway, J.S., 1977, Map and table describing known metalliferous and selected nonmetalliferous mineral deposits in central Alaska: U.S. Geological Survey Open-File Report 77-168-D, 132 p., 1 sheet, scale 1:1,000,000.
|Reporters||C.E. Cameron (Alaska Division of Geological and Geophysical Surveys)|
|Last report date||3/22/2000|