Spokane Mountain

Region West, Northwest
Mineral systems
Deposit types
Other minerals

Information leading to the delineation of this focus area

Basis for focus area Cretaceous quartz monzonite hosts multiple U occurrences (Dahl, Daybreak, Curtin, Morning Sun and others; Huntting, 1957). Limited production is reported from the Dahl mine (Pool, 2017). The focus area was delineated based on host Cretaceous granite and related U occurrences.
Identified resources Historical production of uranium.
Production Dahl mine (1955-1966): 80,000 lbs of U3O8 (Pool, 2017).
Status Past mining.
Estimated resources Unknown.
Geologic maps Weissenborn and Weis (1976), scale 1:62,500; Stoffel and others (1991), scale 1:250,000.
Geophysical data Rank 2 aeromagnetics on western side of focus area (see Blakely and others, 2015); Rank 3 on eastern side; no aeroradiometric data.
Favorable rocks and structures Veins/shear zones in Cretaceous granite.
Deposits Dahl mine (MRDS dep_id: 10056123).
Evidence from mineral occurrences MRDS; International Atomic Energy Agency (2020b); U.S. Environmental Protection Agency (2006).
Geochemical evidence Unknown.
Geophysical evidence Unknown.
Evidence from other sources Multiple uranium occurrences (Daybreak Mine, Morning Sun, Huffman Lease and others) cluster within the Cretaceous intrusive rock in comprising the Mount Spokane Uranium Area.
Comments Focus area listed as a Magmatic REE-Peralkaline syenite/ granite/rhyolite/alaskite/pegmatite. Only known mineralization is uranium. Enrichment of all other critical commodities listed has been inferred from the mineral system/deposit type table (Hofstra and Kreiner, 2020).
Cover thickness and description Exposed at the surface.
Authors Susan Hall, Joshua M. Rosera.
New data needs Geophysics, mapping, and geochemistry.
Geologic mapping and modeling needs Detailed mapping and geochemistry.
Geophysical survey and modeling needs High-resolution, Rank 1 aeromagnetic and aeroradiometric coverage.
Digital elevation data needs Lidar complete (QL3).