|Quadrangle map, 1:250,000-scale||BD|
|Quadrangle map, 1:63,360-scale||B-5|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||May's Pit, as the mine is now commonly known, is on a large flat, now-barren saddle on the divide between the head of Tenderfoot Creek and lower Buckeye Creek. It is about 1.6 miles northeast of Richardson on the Richardson Highway and near the center of the southern boundary of section 14, T. 7 S., R. 7 E., of the Fairbanks Meridian. The location is accurate.|
The Richardson District is characterized by gentle slopes and broad, alluvium-filled valleys (Prindle and Katz, 1913). The area is unglaciated and largely overlain by windblown silt, sand, and loess, locally up to 50 meters thick (Foster and others, 1979). The rocks consist of three structure-bounded units (Weber and others, 1978; Swainbank and others, 1984; Noyes and others, 2006; Freeman, 2011). There is a core that consists mainly of biotite-hornblende-feldspar-quartz gneiss and lesser amphibolite, quartzite, marble and calc-silicate hornfels. The core is bounded on the north and south by amphibolite-grade pelitic schist. The contacts between the units are probably low-angle faults; north-trending vertical faults occur widely. Weber and others (1978) assign the pre-metamorphic age of the rocks to the Precambrian or Paleozoic. They were metamorphosed in the Middle to Late Devonian and recrystallized in the Early Cretaceous (Dusel-Bacon and others, 2004; Freeman, 2011). The metamorphic rocks are intruded by 90 Ma, felsic to intermediate dikes and plugs, notable the mineralized quartz-feldspar porphyry dike at the nearby Democrat Mine (BD014).
The May's Pit residual placer was found in 1908 by Fred Campbell but mining was stymied for 40 years because of the lack of water. Campbell transported ore downhill to Hinkley Gulch for processing (Olson and others, 1985; May, 2005, Freeman, 2011). In 1948 or 1949, Campbell leased the ground to Gib Martin who mined the property as an open pit with a dozer. As related by Freeman (2011), another miner said that he had seen an estimated 4,500 ounces of gold that came from the final cleanup of Martin's mining. Subsequently, the ground was leased to Gil Monroe and Erick Erickson who mined the property until 1978. In 1979, Don May of Polar Mining acquire the property. He worked the property as an open pit with a dozer from 1979 to 1981 and recovered 8,000 ounces of gold.In 1988, Asarco drilled a hole at least 330 feet deep in the center of May’s pit (Applegate, 1988). Most of the hole was in biotite-muscovite schist and biotite-feldspar-quartz gneiss; a quartz-feldspar-porphyry dike about 5 feet thick was cut and the hole bottomed in mylonite. The hole intersected a few thin quartz veins with pyrite selvages but no sample from the hole produced as much as 0.002 ounce of gold per ton. In 2005, an extensive soil sampling program that extended over the property into upper Tenderfoot Creek defined several areas that were anomalous in gold, silver, arsenic, bismuth, tin, tungsten, copper, lead, and zinc (Noyes and others, 2006). The anomalies were less pronounced over May’s Pit. Freeman (2011) suggests that May’s Pit may be above a distal intrusion-related gold deposit similar to the one at the Democrat Mine (BD014).
|Geologic map unit||(-146.302555349979, 64.3003929328806)|
|Mineral deposit model||Residual gold placer, possibly above or near an intrusion-related gold deposit.|
|Mineral deposit model number||39a|
|Age of mineralization||Quaternary?|
|Alteration of deposit||Possible alteration of intrusive and/or schistose host rocks to kaolinite (Swainbank and others, 1984).|
|Workings or exploration||The May's Pit residual placer was found in 1908 by Fred Campbell but mining was stymied for 40 years because of the lack of water. Campbell transported ore downhill to Hinkley Gulch for processing (Olson and others, 1985; May, 2005; Freeman, 2011). In 1948 or 1949, Campbell leased the ground to Gib Martin who mined the property as an open pit with a dozer. Subsequently, the ground was leased to Gil Monroe and Erick Erickson who mined the property until 1978. In 1979, Don May of Polar Mining acquired the property and he mined an open pit with a dozer from 1979 to 1981. In 1988, Asarco drilled a hole at least 330 feet deep in the center of May’s pit (Applegate, 1988). In 2005, an extensive soil sampling program covered the mine and extended into upper Tenderfoot Creek.|
|Indication of production||Yes; medium|
|Production notes||Production of 8,000 ounces of gold from 1979 to 1981 is documented. Another 4,500 ounces reportedly was produced and there may have been significantly more.|
Bundtzen, T.K., and Reger, R.D., 1977, The Richardson lineament--A structural control for gold deposits in the Richardson mining district, Alaska, in Short notes on Alaskan Geology, 1977: Alaska Division of Geological and Geophysical Surveys Geologic Report 55, p. 29-34.
Dusel-Bacon, C., Wooden, J.L. and Layer, P.W., 2004, A Cretaceous Ion-Microprobe U-Pb zircon Age for the West Point Orthogneiss: Evidence for another Gneiss Dome in the Yukon-Tanana Upland in Galloway, J.P., ed., 2004, Studies by the U.S. Geological Survey in Alaska, 2001: U.S. Geological Survey Professional Paper 1678, p. 41 - 60.
Freeman, C.J., 2011, Geology and mineralization of the Richardson gold property, Richardson Mining District, Alaska: Geologic report for Select Resources Corp. Inc., http://tri-valleycorp.com/docs/NI_43-101_Report.pdf (as of February 24, 2012).
May, D.J., Sr., 2005, A brief history regarding the Ridge Top and Hinkley Gulch gold deposits, Richardson District, Alaska: Unpublished report, 18 p.
McCoy, D.T.; Newberry, R.J.; Layer, P., DiMarchi, J.; Bakke, A.; Masterman, J.S. and Minehane, D.L., 1997, Plutonic-related gold deposits of interior Alaska: in Economic Geology Monograph 9, p. 191-241.
Olson, B.G., Burton, J., Wolff, E.N., and Swainbank, D., 1985, Mining and minerals in the golden heart of Alaska: Fairbanks North Star Borough Publication, 80 p.
|Reporters||Cameron S. Rombach (ADGGS); D.J. Grybeck (Contractor, USGS)|
|Last report date||4/1/2012|