JOHANNESBURG (miningweekly.com) – A recent exploration and drilling programme at Ivanhoe Mines’ Kamoa copper property, in the Democratic Republic of Congo (DRC), has confirmed the 2012 indicated resource estimate of 739-million tonnes, grading 2.67% copper, containing 43.5-billion pounds of the metal.
While the existing resource had traditionally been cited at a 1% cutoff, recent drilling showed that grade continuity exists at a 1.5% cutoff, which should enable selective mining of higher-grade areas in early years and, thus, improve the economics.
Infill drilling continued, which would be fed into an upcoming prefeasibility study.
Analysts at Griffiths McBurney (GMP) Securities described the results as “useful”, as high-grade continuity could materially improve the early years’ grade and the project’s economics.
GMP Securities mining analyst Brock Salier said while the infill results were of “little materiality”, the fact that the higher-grade zones had good continuity was a “useful addition”.
“This means that once the bankable feasibility study, including detailed mine plan, is completed, the potential exists for Ivanhoe to selectively mine the higher-grade ore in the early years, depending on the mining method.
“The impact to economics is less clear though, given that the existing 2013 preliminary economic assessment already incorporates a life-of-mine headgrade of 3% copper – but perhaps this can be improved on,” he commented.