In this work, a group contribution model to predict the behavior of mineral concentration circuits is presented. The new model is an expansion and modification of an existing model in the literature (Sepulveda 2014). The modifications extend the number of process groups from 35 to 143, which makes it possible to extend the number of concentration circuits that can be represented from 1492 to over 274 million circuits and to increase the maximum number of stages from 6 to 9. The errors observed between the fitting and the prediction results of concentration circuits that were not included in the fitting verifies that the new model could be extremely useful in the design of mineral concentration circuits. (C) 2014 Elsevier Ltd. All rights reserved.