A thorough knowledge of mineralogy obtained at appropriate scales of observation is essential to resolve questions of ore genesis, as much as to ensure optimized recovery and efficient processing with minimal use of energy, water and chemicals. Mineralogy and other physical characteristics of an ore can have a profound impact on the value of a mining project, as well as its economic viability and ESG footprint. Mineralogical knowledge can also underpin innovation in extraction technologies designed to maximize the value of complex ores. These statements are especially true for critical minerals (CM, an emerging class of commodities, essentially metals and some non-metals), which may, as in the case of rare earth elements (REEs), occur as a diverse number of different mineral phases, or may not form independent minerals at all but rather are typically hosted within major ore minerals (e.g. In, Ga, Ge, and in some cases, Co and Ni). Comprehensive mineral characterization is also invaluable to understand the deportment and distribution of associated non-target components, e.g., U, Th, and daughter radionuclides associated with REE-minerals, the adverse impact which minor components can have on a mineral’s physical properties (e.g., floatability), as well as for understanding how the mineralogy of CMs may evolve over geological time in response to superimposed geological events, or during different stages of processing. The contribution shows different approaches to the characterization of CMs in geological materials and their anthropogenic analogues. We draw on examples from ongoing research on ores of different genetic types, as well as work targeting the distribution and behavior of selected CMs in ores and through flotation-leaching-smelting-electrorefining operations at Olympic Dam.