Defining an alkaline igneous-associated REE-HFSE mineral system: A foundation to map plays, uncertainty and risks to project value

REE-HFSE exploration and research projects tend to focus on describing deposit- to outcrop-scale mineralisation. Regional-scale frameworks, mineral system maps and predictive targeting capability are largely lacking. A contextual, probabilistic REE-HFSE mineral system approach is being developed by the authors to enable any RFE-HFSE mineral system's extent to be defined, mapped and 'risked' in 4D. This will enable systematic investigation of the crustal pathways and potential trap locations along which a mantle-derived REE-HFSE 'batch' may now be distributed. A workflow to define any REE-HFSE mineral system is presented: (a) Identify and hierarchically organize a mineral system's genetically related sub-divisions and deposits, (b) map its known and possible maximum extents, (c) name it, (d) discern its known mineral endowment, and (e) assess the favourability of the system's critical components for preserving project value. The workflow is designed to improve predictive targeting along under-evaluated plays, in order to prioritise further investigations and expenditure. It provides the foundation to compare, risk, and rank REE-HFSE provinces, plays and projects. And it is easily adaptable for other mineral commodities.