Preliminary Economic Assessment

Stage 3 of 8

Preliminary Economic Assessment — a first-pass, lower-confidence study of whether the deposit could be economic to mine, used to justify further spending.

A Preliminary Economic Assessment (PEA) is the first formal look at whether a deposit could be economically mined. It uses conceptual mine designs, order-of-magnitude cost estimates, and often assumes some material currently only in the Inferred category, so it carries low confidence — regulators require it to be labeled as such. Its purpose is to give the company (and investors) a first read on project economics — NPV, IRR, payback — to justify spending on the more rigorous, expensive studies that follow. A strong PEA is a green light to keep advancing; a weak one often kills a project outright.