Mike Clarke with Augusta Resources described an area north of the proposed Rosemont copper mine as an "excellent target" for an underground mining operation, with ore containing up to 1.3% copper. Drilling is underway now around the old Narragansett mine workings, a half mile or so north of the proposed boundary of the Rosemont pit. He also indicated that Augusta is looking for additional targets in the area that may be hidden by faulting.
Mike made his comments in a technical talk at the SME Tucson conference on Monday at the El Conquistador Resort. Attendance was over 380.
Mike's talk offered reconstruction of the structural history of the Rosemont geology, with an early down-to-the-west normal fault that decapitated the igneous intrusion, and after a large rotation, now gives the confusing appearance of a west-verging thrust fault.
Despite a hundred years (plus or minus) of mineral exploration across this section of the Santa Ritas, it's amazing to see what careful geologic exploration can discover.