Mineral Processing Testwork refers to the systematic laboratory and pilot-scale experimental program conducted to determine how ore from a mineral deposit responds to various processing methods, and to generate the data required to design, size, and optimize a full-scale mineral processing plant. Testwork is initiated during the early stages of project development and continues through feasibility studies, plant design, and operational optimization. It is one of the most critical components of a bankable feasibility study (BFS) because it directly influences capital and operating cost estimates, plant design parameters, and projected mineral recoveries. A comprehensive testwork program includes comminution tests (Bond ball and rod mill work indices, drop weight tests, JK rotary breakage testing, SMC tests) to define grinding energy requirements and equipment sizing; mineralogical characterization to identify mineral assemblages and liberation size; gravity concentration tests; flotation kinetic and locked cycle tests to determine reagent suites, grind size, and circuit configuration; leach tests (bottle roll tests, column leach tests for heap leach feasibility); and thickening and filtration tests to size solid-liquid separation equipment. For gold refractory ores, testwork may include whole ore roasting, BIOX, or POX pre-oxidation experiments. Diamond testwork focuses on liberation tests using low-energy crushing and scrubbing trials, and DMS sink-float tests. In bauxite projects, Bayer process digestibility testwork defines digestion conditions and alumina recovery. Results of mineral processing testwork underpin recovery models and process design criteria, and are audited by independent metallurgical specialists as part of project due diligence.
