Judith Mountains

Region West, Northwest
Mineral systems
Deposit types
Other minerals

Information leading to the delineation of this focus area

Basis for focus area Deposit types are metallic-lode deposits including intrusive complexes, carbonate replacements, veins in igneous rocks, skarns, disseminated deposits hosted by intrusives. Historical production was from Au-Ag telluride quartz veins.
Identified resources Identified resources for gold. Historical production of gold, silver, and base metals.
Production Unknown.
Status Past mining.
Estimated resources Gies mine (1990): Demonstrated reserves of 43,545 mt of ore with a grade of 9.3g/mt Au.
Geologic maps Goddard (1988), scale 1:31,680.
Geophysical data Inadequate aeromagnetic and aeroradiometric coverage.
Favorable rocks and structures Intrusive rocks associated with the gold telluride veins. Alkali-calcic suite: quartz monzonite, monzonite, quartz diorite, diorite, syenite and rhyolite. Alkaline suite: alkali gabbro, syenite, ijolitic rocks, gray tinguaite, green tinguaite, carbonatite (?) with associated fenite and alkali granite.
Deposits Gies mine (MRDS dep_id: 10196569), Spotted Horse mine (MRDS dep_id: 10071386), Maginnis mine (MRDS dep_id: 10071340).
Evidence from mineral occurrences MRDS.
Geochemical evidence Minor Te, V, and Zn which are known to occur in gold telluride veins in the focus area.
Geophysical evidence Unknown.
Evidence from other sources None.
Comments A variety of telluride minerals are found in the gold veins. In other districts Te is recovered as a byproduct of gold mining. The intrusions could also be a source for other critical minerals. Even though critical minerals were not produced there is a possibility that the intrusions associated with the gold telluride veins could be a source of critical minerals. The remaining gold-telluride veins could be a source for Te and V. Deposit type tentatively classified as low sulfidation on the basis of V and F occurrences in the focus area. Occurrence of Bi, Ga, Ge, and In are possible in this mineral system/deposit type table (Hofstra and Kreiner, 2020), but more information is required to determine their abundances in this focus area.
Cover thickness and description Exposed at the surface.
Authors Stanley L. Korzeb, Kaleb C. Scarberry, Jay A. Gunderson, Joshua M. Rosera, Allen K. Andersen.
New data needs High resolution geophysics, whole-rock geochemistry for all critical minerals, geologic mapping, lidar.
Geologic mapping and modeling needs 1:24,000 scale geologic mapping.
Geophysical survey and modeling needs High resolution aeromagnetic and aeroradiometric coverage.
Digital elevation data needs Lidar in progress only over western third; rest has no lidar coverage.