May's Pit

Mine, Active

Alternative names

Campbell-Monroe
Campbell

Commodities and mineralogy

Main commodities Au
Ore minerals gold
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale BD
Quadrangle map, 1:63,360-scale B-5
Latitude 64.3008
Longitude -146.3002
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.

Geologic setting

Geologic description

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).

Production and reserves

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
Reserve estimates Unknown.
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.

References

References

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