Pre-feasibility studies (PFS) are used mainly for due diligence work helping project developers determine whether or not to proceed with Detailed Feasibility Studies. PFSs are done by factoring known unit costs and estimating gross dimensions or quantities once Preliminary Economic Assessments (PEA) or scoping studies have been completed. PFSs use project specific metrics and this is what sets them apart from PEAs, which are generally based on industry standards rather than derived from detailed site-specific data.
PFSs include options for the technical and economic aspects of a project and are used to identify whether or not continuing exploration for example for mining and oil&gas projects or to attract a joint venture partner.