Gold Mountain Mining District (Kimberly Mining District), Deer Creek, Piute County, Utah, USAi

Regional Level Types
Gold Mountain Mining District (Kimberly Mining District)	Mining District
Deer Creek	Creek
Piute County	County
Utah	State
USA	Country

The Gold Mountain (Kimberly) mining district lies on the northeast flank of the Tushar Mountains about 20 mi northeast of Beaver in northern Piute County of southwestern Utah. The mineralization in the Gold Mountain district was discovered in 1888 when prominent Au-bearing veins were located between 8000 and 10,600 ft elevation. The district was organized in 1889 and remained intermittently productive into the 1950s. Total district metal production at modern metal prices is estimated at $180 million. Due to the rugged terrain, the mines were primarily accessed by a series of adits (Lindgren, 1906). The district was a large Au producer and the Annie Laurie and Sevier mines were the largest producers.
The Gold Mountain district lies on the north flank of the Marysvale volcanic field of the transition zone between the Basin and Range Province and the Colorado Plateau. The district is localized around the Kimberly quartz monzonite plug (about 24 Ma) that intrudes the coeval Oligocene-Miocene Bullion Canyon Group volcanic rocks just north of the Mount Belknap caldera. The Kimberly quartz monzonite is a medium-grained, equigranular to strongly porphyritic plug.
There are two main mines in the Gold Mountain district: the Annie Laurie on the east and the Sevier about a mile to the west. These mines host north-northwest-trending vein sets that appear to outline a northwest-trending graben in the host quartz monzonite. The Annie Laurie vein trends about N. 20° W., 55° SW. and the Sevier trends roughly N. 15° W., 65° NE. The orebodies are low-sulfidation, epithermal, white, quartz-carbonate ±adularia veins with minor fluorite and barite (USGS Model 25b). The veins are primarily oxidized where they have been exploited. Primary ore minerals are rarely visible except for a little argentite and some fine native gold seen upon crushing and panning the ore (Lindgren, 1906; Park and Krahulec, 2009).
A series of three exploration programs from 1981 to 1996 attempted to evaluate the remaining Au resources in the district, primarily at the Annie Laurie and Sevier mine areas. A total of 38 holes were drilled during these programs. These exploration programs partially delineated two subeconomic inferred resources: about 200,000 tons of 0.55 ppm Au and 62 ppm Ag in the lower Kimberly mill tailings and a crudely estimated 100,000 tons of 5.14 ppm Au and 51.4 ppm Ag in the lower Annie Laurie mine (Park and Krahulec, 2009). In addition to Au and Ag, the veins are anomalous in Pb, Zn, and Cu. While all past metal mining and documented exploration in the Gold Mountain district has been directed toward Au-Ag, other potential exploration targets may exist. The central area of pervasive argillic alteration in the Kimberly quartz monzonite (about 0.14 sq mi) and the elevated Mo rock-chip anomalies (to 434 ppm Mo) could indicate a porphyry Mo (-Cu) system at depth (Park and Krahulec, 2009).