Excelsior Mining (TSX: MIN) issued a statement saying that initial copper recovery grades at the Gunnison project in southern Arizona are exceeding the expectations presented in the property’s feasibility study.
According to Excelsior, pregnant leach solution grade is currently measuring 0.15 grams per litre of copper in the primary recovery pond.
“This milestone is ahead of schedule and keeps Excelsior on pace for copper production this quarter,” the release states.
The Phoenix-based miner explained that acid injection is being steadily increased and is currently at approximately 50% of the full production rate.
“The 41 injection and recovery wells that comprise the production wellfield will continue to circulate mining solutions (over a cubic area of approximately 400ft x 400ft x 700ft) in a closed-loop system until the concentration of copper held in solution warrants processing.”
Excelsior said that once this grade is achieved, mining solutions will then be treated through the Johnson Camp processing facilities to extract copper and produce LME grade copper cathode sheets.
This means that first copper cathode sales should be expected in Q1, 2020.