The simultaneous extraction of several metals is a common phenomenon when metals occur together in nature. This is the case of platinum group metals (PGMs) -composed by Pt, Pd, Rh, Ru, Ir and Os-, nickel and copper, whose main deposits and reserves are in South Africa and Russia. Due to the growing demand for these elements, it is important to study the energy cost of their extraction and the different possibilities of allocating these costs. In this paper, the allocation of costs has been analyzed following economic criteria, which is the main method used in Life Cycle Assessments (LCA) -taking different prices depending on the time period-, geological criteria -taking into account the geological scarcity of the elements- or through their exergy replacement cost (ERC) -the cost of replacing an element from a total state of dispersion, in Thanatia, to the current mines-. The geological and ERC methods provide a cost allocation methodology with a strictly physical vision, avoiding time-varying factors such as the economic cost of the elements in the market.