|Quadrangle map, 1:250,000-scale||RB|
|Quadrangle map, 1:63,360-scale||B-5|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||Monument Creek flows through the southwestern corner of the Ruby (B-5) Quadrangle. The area of interest is approximately 5 1/2 miles south of VABM Monument (USGS topographic map, 1952, minor revisions in 1973), which corresponds to location 24 of Cobb (1972 [MF405]). Coordinates are for the approximate midpoint of placer ground in section 13, T. 14 S., R. 17 E. of the Kateel River meridian. The placer ground extends for about a mile downstream from a point 1/2 mile above the tributary Rabbit Creek. The discovery claim was made at the mouth of Rabbit Creek. The location is accurate.|
The bedrock underlying Monument Creek is likely intermediate to mafic intrusive rocks (Puchner and others, 1998). Granite is present on a headwater divide to the north of the creek, and rocks peripheral to this body may be the source of the metals in the placer gravels (Eberlein and others, 1977).
Gold was discovered along Monument Creek during the winter of 1912-13 (Eakin, 1914). About 1,450 ounces of gold and some byproduct silver were recovered between 1913 and 1933 (Mertie, 1936). Monument Creek was also explored from 1990 to 1993 (Swainbank and others, 1991; Bundtzen and others, 1992; Swainbank and others, 1993; Swainbank and others, 1995).The gold is found in an irregular, spotty pay streak 20 to 50 feet wide, about 1/2 mile above and below the mouth of Rabbit Creek (Mertie, 1936). At 1/4 mile below the mouth of Rabbit Creek (Discovery claim) 25 feet of muck is underlain by 15 feet of gravel. Gold is found in irregularly distributed, 3-to-6-inch-thick streaks of fine gravel. There is little or no gold on bedrock (Mertie, 1936). The gold is both fine and coarse, and the largest nugget weighed a little more than an ounce. The average of three assays showed 853 parts gold per thousand and 139 parts silver per thousand (Mertie, 1936). Cassiterite is also present with the gold (Mertie and Harrington, 1916; Chapin, 1919; Joesting, 1942).
|Geologic map unit||(-155.430577023851, 64.2688575605071)|
|Mineral deposit model||Placer Au (Cox and Singer, 1986; model 39a).|
|Mineral deposit model number||39a|
|Age of mineralization||Quaternary.|
|Workings or exploration||Monument Creek was mined from 1913 to about 1933 (Mertie, 1936) and from 1990 to 1994 (Swainbank and others, 1991; Bundtzen and others, 1992; Swainbank and others, 1993; Swainbank and others, 1995).|
|Indication of production||Yes; small|
|Production notes||Total production for Monument Creek through 1933 was about 1,450 ounces (Mertie, 1936).|
Bundtzen, T.K., Swainbank, R.C., Wood, J.E., Clough, A.H., 1991 (1992), Alaska's Mineral Industry 1991: Alaska Division of Geological & Geophysical Surveys, Special Report 46, 89 p.
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.
Eakin, H.M., 1914, Placer mining in the Ruby district: U.S. Geological Survey Bulletin 592-J, p. 363-369.
Joesting, H.R., 1942, Strategic mineral occurrences in interior Alaska: Alaska Territorial Department of Mines Pamphlet 1, 50 p.
Mertie, J.B., Jr., 1936, Mineral deposits of the Ruby-Kuskokwim region, Alaska: U.S. Geological Survey Bulletin 864-C, p. 115-245.
Mertie, J.B., Jr., and Harrington, G.L., 1916, Mineral resources of the Ruby-Kuskokwim region, in Brooks, A.H., and others, Mineral Resources of Alaska, Report on Progress of Investigations in 1915: U.S. Geological Survey Bulletin 642-H, p. 223-266.
Puchner, C.C., Smith, G.M., Flanders, R.W., Crowe, D.E., and McIntyre, S.C., 1998, Bedrock geology of the Ruby-Poorman mining district, Alaska: Alaska Division of Geological and Geophysical Surveys Report of Investigations 98-11, 12 p., 3 sheets, scale 1:63,360.
Swainbank, R.C., Bundtzen, T.K., and Wood, J.E., 1991, Alaska's mineral industry, 1990: Alaska Division of Geological and Geophysical Surveys Special Report 45, 78 p.
Swainbank, R.C., Bundtzen, T.K., Clough, A.H., Hansen, E.W., and Nelson, M.G., 1993, Alaska's Mineral Industry 1992: Alaska Division of Geological and Geophysical Surveys Special Report 47, 80 p.
Swainbank, R.C., Bundtzen, T.K., Clough, A.H., Henning, M.W., and Hansen E.W., 1995, Alaska's mineral industry 1994: Alaska Division of Geological and Geophysical Surveys Special Report 49, 77 p.
|Reporters||C.E. Cameron (Alaska Division of Geological and Geophysical Surveys)|
|Last report date||3/22/2000|