Modreski (1985) and Hughes (Nash, 1989) indicate that copper-cobalt-gold mineralization hosted by the Mesoproterozoic Apple Creek Formation clastics represents synsedimentary or volcanogenic massive sulphides formed at, or near, the sea floor. Mineralization is related to rifting within the basin and is contemporaneous with the emplacement of mafic intrusives into the turbidite sequence represented by the Apple Creek Formation.
Exploration at the CAS Project is primarily focused on this style of mineralization.
Fox and Hulen (1999) described gold-cobalt bearing sulfide rich quartz veins and shears hosted by spotted phyllites in the discovery trench and various road cuts. Mineralized veins and shear zones contain quartz veins and stringers with iron carbonate, cobaltiferous pyrite, arsenopyrite, trace chalcopyrite and tourmaline. Trace element indicators are Au, As, Bi, Co, Cu and possibly Sb. There are three known mineralized zones, A, B, and C from North to South respectively, of this style of mineralization. Zone A has been traced for a distance of 2,000 ft on the surface and is up to 300 ft wide. Zone B has been traced for 2,600 ft on the surface and is up to 400 ft wide. Zone C has been traced for 3,400 ft on the surface and averages 150 ft wide.
The composition and style of mineralization is similar to the stringer zone mineralization associated with stratabound copper-cobalt mineralization at the nearby Blackpine Mine, located 10 kilometers to the northwest. Modreski (1985) describes mineralization at Blackpine as comprising pyrite-chalcopyrite-arsenopyrite in veinlets and stringers grossly stratiform within chlorite-biotite-muscovite siltite and quartzite. Cobalt mineralization is also found remobilized along shear zones parallel to bedding and in silicified and tourmalinized breccias at other locations within the Idaho Cobalt Belt.
The cobalt/copper occurrence on the property was discovered in 1967. Recon surface geologic work was conducted by Sachem Corporation (1970-1973), Noranda Exploration (1977-1982), Kinross Gold (1989-2000) and Thunder Mountain Gold (2011). Nevada Contract Corporation (2002-2004) and Salmon River Resources (2005) conducted drilling operations on the property.
Drilling on the property has encountered strong mineral occurrences of cobalt and gold. Results include:
- IC03-03 1.5m @ 0.54% Co and 8.5g/t Au
- IC03-04 4.6m @ 0.34% Co and 8.3g/t Au
- IC03-07 3.0m @ 0.08% Co and 9.2g/t Au