This paper describes the parameterization of a discrete batch grinding equation based on mass. The approach has been to match the zero and first moments of the discrete batch grinding equation with that of the corresponding continuous solution. A new parameterization of the discrete equations is obtained where the discrete selection function has a different rate constant for each discrete interval. A simple test problem is used to determine the accuracy of the discretization procedures. The model is used to obtain new parameters on a discrete root 2 mesh for dolomite, limestone and gold bearing ore.