THE CUDDY MOUNTAIN PORPHYRY CU-MO (AU) SYSTEM: THE REVIVAL OF THE OFT-FORGOTTEN BLUE MOUNTAINS MINERAL BELT IN WESTERN IDAHO

The Cuddy Mountain porphyry Cu-Mo (Au) project is located 20 km NW of Cambridge, Idaho, and is hosted within a series of Triassic to Jurassic volcanic and volcaniclastic rocks of the Blue Mountains Province. This region has previously been known to host other magmatic-hydrothermal and volcanogenic massive sulfide deposits in western Idaho and northeastern Oregon. Interest in this district has recently been renewed with the blind discovery of the Leviathan porphyry Cu deposit by Hercules Silver Corp. in 2023. Historic exploration at Cuddy Mountain has previously identified a mineralized porphyry Cu occurrence, referred to as the IXL mine. The porphyry Cu mineralization at the IXL mine is associated with sheeted to stockwork cm-scale quartz-chalcopyrite ± bornite ± molybdenite veins associated with hydrothermal K-feldspar and biotite alteration of the wall rock, and large areas of adjoining quartz-sericite-pyrite mineralization. Previous studies suggest this mineralization is associated with intrusion of a Jurassic-aged ~10 km² multi-phase equigranular quartz diorite to granodiorite pluton associated with crowded granite porphyries. Initial field mapping completed by Scout Discoveries Corp. in 2023 suggests the mineralized porphyry system is likely tilted (~60-80°) to the northwest based on the mapped distribution of hydrothermal alteration and dip of high-temperature sheeted quartz veins at surface. Additionally, the presence of widespread albite-actinolite alteration of the pluton and presence of massive barite in the gangue mineralogy at the Climax and Iron prospects suggests that external meteoric brines may have locally remobilized copper, forming high-grade lode deposits. Accordingly, we suggest that the Jurassic-aged Yerington district is the best analog for the magmatic and hydrothermal systems that formed the mineral deposits at Cuddy Mountain. Based on our recent and ongoing work at Cuddy Mountain, and the recent discovery of the adjoining Leviathan porphyry Cu deposit, we believe that the Cuddy Mountain project is part of a Jurassic-aged porphyry Cu cluster. We suggest magmatic-hydrothermal systems within the Blue Mountain Province represent an extension to the well-endowed Jurassic-aged porphyry Cu mineral province of British Columbia extending south through Yerington, Nevada.