What is a Preliminary Economic Assessment (PEA)?

A Preliminary Economic Assessment — also called a scoping study — is the earliest formal economic evaluation of a project under NI 43-101. It models capital cost, operating cost, production rate, and outputs headline economics: net present value (NPV), internal rate of return (IRR), and payback.

The PEA's defining feature is that it may include Inferred resources, the lowest-confidence category. That makes it valuable for showing a project's potential shape — but the rules require every PEA to carry a warning that it is preliminary, that there is no certainty it will be realised, and that Inferred material is too speculative to have economics applied with confidence.

For investors: a PEA tells you whether a project is worth advancing, not whether it will be built. Treat PEA-stage NPVs as optimistic sketches. Confidence rises with a Pre-Feasibility and Feasibility Study, which exclude Inferred material and tighten the engineering.