The Mud Springs prospect claims are located in the Silver Peak Range, approximately 14 miles west of the town of Silver Peak in the “Red Mountain” Mining District. The five lode claims (SUN) are situated about 27 miles from Silver Peak, via improved gravel roads and dry washes. Elevations at the prospect range from approximately 6000 to 8266 feet (1828-2519 m).
Bulk-mineable, volcanic-hosted, gold and silver mineralization associated with resurgent domes interior to the margins of a Tertiary-age caldera.
Several companies have held claims in the vicinity of the SUN claims. Sunshine Mining conducted sampling at Mud Springs, in conjunction with exploration activities three miles northeast at Argentite Canyon in the 1970’s. An assessment of the mineral resources of the proposed Silver Peak Wilderness Study Area was published in 1988 and includes a brief discussion of the Mud Springs prospect and a general summary of the regional geology in the vicinity of Mud Springs. At that time, there were bulldozer trenches and drill sites prepared at the prospect. No other details of this exploration are known. In 1990, a small company from Silver City, Nevada, carried on exploration activities that included roadbuilding; details of their efforts are unknown.
The geology of the region is described by the USGS in several published reports and in Sunshine Mining reports. The Silver Peak Range is an arcuate mountain range cored by Precambrian to Paleozoic metasedimentary rocks that are intruded by Mesozoic plutonic rocks. Tertiary-age, felsic volcanic rocks are the mostly widely exposed rock units in the range and include flows, tuffs and intrusives. SMC describes the geology of the range as being a northwest-trending “sag” in the pre-Tertiary rocks filled by Tertiary volcanics and volcaniclastics rocks. The geologic map pattern of the “sag” suggests folding of the pre-Tertiary rocks along a NW -structural grain. SMC describes the geology of the range as being a northwest-trending “sag” in the pre-Tertiary rocks filled by Tertiary volcanics and volcaniclastics rocks. The geologic map pattern of the “sag” suggests folding of the pre-Tertiary rocks along a NW -structural grain.
The structure of the range is likely influenced by both the northwest-trending Walker Lane belt and the Silver Peak caldera. The total area of the caldera is approximately 35 square miles; the eastern margin generally coincides with the Silver Peak mining district. The Mud Springs prospect is near the center of the center of the caldera.
The local geology of Mud Springs includes 5.9 m.y. porphyritic latite and trachyandesite that fill the Silver Peak caldera. Just south of the claims, a more coarse-grained, younger latite flow (or plug) is present. The area of the SUN claims is well-summarized in the assessment of the WSA as follows: “an east-trending, 80 to 90°N.-dipping zone of altered, limonitic rhyolite that is overlain by nearly horizontal latite. Zone is 400 to 800 feet wide and crops out for about 1.5 mi. Rocks along zone are sheared, propylitically and argillically altered, silicified, limonitic, and contain epithermal quartz veins and manganese oxide.”
The mineralization in the Red Mountain mining district has been described in the USGS Bulletin 1423 (1977) which includes the Mud Springs prospect but is focused on examples from the Nivloc and Mohawk mines where sheeted, quartz-calcite fissure veins carry silver and lesser amounts of gold, lead, zinc, and copper. The Sixteen to One mine produced silver ores from epithermal veins as well. The controls of mineralization for the mines are similar. Veins have northeast strikes and steep dips have controlled the precious metals mineralization. The veins at the Nivloc mine are quite persistent to depth and although the veins become narrower, persist in the basement rocks beneath the Tertiary host rocks to depths of 1300 feet. The average grades were 11 opt Ag and 0.050 opt Au. The Mohawk mine had ore that averaged 20 to 25 opt Ag and produced over 1.9 million ounces of silver over an intermittent mine life. The Sanger mine reportedly has a resource of more than 1.5 million ounces of silver but no reference could be found that substantiated this resource. Inspiration Copper had the Sanger mine in 1980’s and conducted underground work to reach the vein. Average grades ranged from nine to twenty opt Ag. Declining metal prices, however, forced closure of the mine. This is the only known production since being located in the 1920’s.
Open file reports available from the Nevada Bureau of Mines and Geology include minor references to the mineralization investigated by Sunshine Mining in the 1970’s. An internal report, Argentite Canyon Project (1974, R.A. Forrest) reports indicate that they delineated an arsenic anomaly at Mud Springs. Assays in the report note that one rock chip sample, a bleached felsic rock with strong jarosite, contains a 0.015 opt Au (0.51 g/t) value. Silver in the sample was below detection suggesting that the sample may represent a higher gold to silver ratio than elsewhere in the district.
Geologic mapping of the rock units with an alteration overlay is planned for the Mud Springs prospect. Systematic rock chip or soils grid-sampling will be completed over the color anomaly to determine the distribution and concentrations of trace elements associated with epithermal precious metals deposits.