Copper Exploration by Large Companies Is Essential

The estimated global demand for Cu by 2050 arguably cannot be met under any presently obvious mining scenario. An ill-conceived exploration strategy that relied substantially on junior explorers to discover orebodies that large companies would then purchase, develop, and mine has failed to deliver the required number of new Cu mines. Copper supply after 2050 will require reinvigorated exploration by large mining companies, beyond their present Cu mines. Of the numerous exploration discovery trends during the period 1900 to 2023, 12 have been identified as providing a credible basis for developing the strategy and tactics that will be needed by large companies to re-establish the Cu discovery dominance they held prior to the 1980s. Since porphyry Cu deposits presently supply ~70% of the world’s mined Cu, and they contributed 48% numerically and 71% by contained metal to all Cu discoveries from 1900 to 2023, we propose that they be the primary target of large company exploration, with a focus on deposits that will be mined by a caving method. The fallacy of perceived exploration maturity of some Cu districts was clearly established by Anglo American’s discovery successes in Chile from 1999 to 2010, and we suggest that the southwestern USA porphyry districts, for example, which contain a huge known Cu endowment and where at least eight deposits were mined by caving by 1965, rank as a high priority. An attraction of the USA is that it also ranks in the top 20% of countries for exploration as measured by the Fragile States Index. It is recommended that five proposed discovery performance management metrics be applied to measure future porphyry Cu discovery success: (1) a mine development capital intensity ($/tonne [t] of annual Cu production) roughly equal to the prevailing Cu price; (2) a projected minimum mining internal rate of return for a discovered orebody of at least twice the long-term US bond rate; (3) projected cash and total mining and mineral processing costs for a discovered and mined deposit in the lowest quartile; (4) an average ore grade of >0.75 wt % Cu equiv, because of the greater development and premining costs of mining by caving; and (5) an exploration cost/t overall of discovered Cu in ore of <10% of the Cu price at the time. Moreover, it is suggested that large companies adopt a probability decision-making approach to the discovery task.