04/18/2026
There's a contradiction built into how the mining industry evaluates its projects.
A Preliminary Economic Assessment can include Inferred mineral resources in its mine plan and economic model. The numbers look compelling. Then the feasibility study arrives and the same project looks materially different, not because anything went wrong, but because the rules just got stricter.
Inferred resources occupy a double life in mine studies: market-moving at the PEA stage, yet too geologically uncertain to form a production decision or attract project finance. Understanding how that contradiction exists and how it impacts project economics, permitting strategy, and investor expectations is essential for those evaluating mining assets.
I'll discuss this in more detail in my latest blog post. https://kuchling.com/the-double-life-of-inferred-resources/