Faculty of Engineering and the Built Environment; Master of Science in Engineering; Research Report / The primary objective of this study was to develop a methodology for evaluating how the reliability profile of the typical South African Platinum concentrator plant is affected by firstly the size of the primary milling units incorporated in the circuit and secondly by the way that the primary milling units are configured. A methodology, together with a set of general expressions is presented which considers the Platinum concentrator as a stochastic process where the behaviour of the primary mill is a direct measure of the failure pattern of the overall concentrator. The reliability, availability and maintainability (RAM) of the primary mill, and hence the overall concentrator, is then determined by a combination of three different Markov models where each Markov model is used to evaluate and measure a separate set of reliability parameters. This approach effectively overcomes the computational complexity associated with large Markov models. The results of two case studies used to validate the methodology do indicate that the reliability, availability and maintainability profiles of large single stream Platinum concentrators could be fundamentally different from the conventional multiple stream primary mill configurations.