Historically, geochemical data collected from drillholes by explorers in South Australia comprised only drill core assays of the targeted commodity or commodities, thus the potential for other critical minerals in existing deposits remains unknown. For this reason, re-sampling and re-assaying of existing drill core from all major projects in South Australia was undertaken to assess their multi-commodity critical mineral prospectivity. A total of 40 deposits was selected representing a variety of mineralisation styles to better define critical mineral potential across South Australia using historic company records and sampling drillholes from the South Australia Drill Core Library in Tonsley.