Uranium deposits are generally classified into types based on host rock, orebody morphology or structural setting. Widely used schemes contain 14 or more deposit types and numerous sub-types. However, groups of deposit types were formed by similar geological and geochemical processes and likely represent 'variations on a theme'. An alternative scheme is presented that recognises the continuum of possible uranium deposit styles between three families of mineral systems: magmatic-related, 'metamorphic'-related, and basin-related. Formation of uranium deposits in each family involves fluids of three end-member type: magmatic-hydrothermal, 'metamorphic' (including diagenetic waters and fluids reacted with metamorphic rocks at elevated temperatures), and surface-derived fluids such as meteoric waters, seawater, lakewater and groundwater. By better understanding the fundamental geological and geochemical processes involved in ore formation in each family of uranium mineral systems, the most important geological 'symptoms' can be recognised and mapped. This mineral systems approach has been applied to magmatic-related uranium systems in Australia. The predictions of potential suggest that the under-representation of magmatic-related uranium resources relative to other parts of the world with similar geology may be due not to low endowment but to lack of discovery.
