Hard-Rock Mining

Once consulted in this space.  McKinsey talks the underlying economic processes of mining.

Digging deeper: Trends in underground hard-rock mining for gold and base metals

July 13, 2021 | Commentary

While underground mining methods show higher cost than open pit, their complexity almost always means that there is opportunity in both productivity and cost improvement.

 Article (5 pages)

Underground hard-rock mining accounts for 40 percent of global mining operations but only 12 percent of run-of-mine (ROM) production.1 Underground mines also tend to be more targeted, more costly, and less productive than open-pit mines. Because the choice of which underground method to deploy is predominantly driven by the geology of the deposit being mined, the operator has little flexibility in choosing the mining method given that the objective is to maximize net asset value over the life of the mine. But given the inherent complexity in underground mining, we frequently uncover improvement opportunities in both productivity and cost. Of these methods, stopping not only is the most common but also delivers the highest overall production share, at almost 50 percent; block caving is one of the least-used methods but is responsible for an outsize share of overall production, at almost 25 percent (Exhibit 1). Again, these underground mining methods are often determined by the deposits and the economics of mining and are, thus, somewhat out of the operator’s control. ... '