Project Summary
Historical resource estimates indicate 8,000 tons of probable ore in sight, with potential for an additional 20,000 tons on the property. The mineralized zone is approximately 70 feet wide at the surface with a stratigraphic thickness of 35 feet. High-grade tungsten mineralization includes reported grades of over 1% WO₃ (tungsten trioxide) with associated gold. The project is in a highly favorable geological environment with strong potential to outline additional resources along strike and at depth.
The Coos Tungsten project is located on a ridge between the Morris claims and Chidago Flat within the Chidago Mining District of the Benton Range, Mono County, California. It lies approximately 11 miles (17.9 km) south-southwest of the town of Benton.
$45,000 + 2% NSROwner financing and payment plans available on request.
Geology
The project targets a contact-metamorphic gold-tungsten (Au-W) deposit within a metasedimentary mass engulfed in granite and alaskite. The host rocks consist of quartz schist and thin-bedded limestone, where lime silicates have developed along the bedding planes. The beds strike N. 18° W. to N. 20° W. and dip 25° NE to 27° NE. The primary ore zone is 70 feet wide at the surface, with a stratigraphic thickness of 35 feet, is cut by a 10-foot-thick rhyolite dike, and is covered by several feet of loose overburden.
Metals of primary economic interest are tungsten and gold. The ore is described as soft, oxidized, and rusty, consisting of calcareous rocks and sericite hornfels in alaskite. Valid mineral species identified within the mineralized zone include scheelite, muscovite (var. sericite), and powellite.
History
Initially held by the J. A. Coos estate, the property was leased to the Bishop Tungsten Company, which initiated development work in 1940 to delimit the extent of the deposit. Development workings on the property include surface trenches and pits, three short adits (including one driven approximately 50 feet below the hill crest to crosscut the ore zone from the north), an open pit, and a shallow inclined shaft.
In a 1940 examination for the USGS Strategic Minerals Investigations geologists concluded “there was about 8,000 tons of probable ore in sight, and there might be another 20,000 tons of ore on the property.”
While early operations were focused on defining the immediate near-surface tonnage, the favorable limestone beds remain highly prospective for modern systematic exploration to test for deeper extensions.