Mining project assessment typically progresses in stages—from preliminary economic assessment (PEA) and prefeasibility study (PFS) to feasibility study (FS) levels —with each stage delivering greater engineering detail and cost accuracy. SRK provides metallurgical development support for a wide range of commodities including gold, silver, copper, lead, zinc, iron, tin, tungsten, molybdenum, lithium, rare earth elements and various industrial minerals. At each study level, SRK assists with the preparation of metallurgical sample composites, laboratory selection, coordination and management of testwork, and preparation of final metallurgical reports and technical sections.
A PEA metallurgical program is designed to be cost-efficient, relying on limited sampling and, where available, existing material. Typical testwork includes head and mineralogical analyses, comminution testing, and bench-scale tests for process characterization.
The results provide an early indication of achievable metal recoveries using generalized test procedures appropriate to the ore type being evaluated and support the development of an initial conceptual process flowsheet.
A PFS metallurgical program provides a more detailed evaluation of process requirements and supports the development of preliminary design criteria and process flowsheet. Building on the findings from the PEA, it is typically conducted on selected core intervals to prepare one or more master composites representing the deposit and identified ore types. Testwork commonly includes head and mineralogical analyses, comminution testing, bench-scale tests across a range of process parameters and thickening and filtration studies. Initial tailings characterization is often conducted to generate data for early-stage environmental permitting.
An FS metallurgical program provides definitive process design criteria and finalized flowsheet. Building on PFS findings, it is based on master and variability composites prepared from selected core intervals representing the deposit main ore types. Variability samples are tested across grades, lithologies, and ore zones to assess response to optimized process parameters developed from master composites. For this program, testwork includes head and mineralogical analyses, comminution and bench-scale testing and thickening and filtration studies. Locked-cycle flotation tests evaluate the impact of recycling intermediate products and process water on recovery and product grades, while pilot testing is undertaken where new processes or large intermediate product quantities warrant further downstream evaluation. Detailed tailing characterization is also generally completed at this stage in close coordination with environmental teams responsible for project permitting.
