Worldwide mineral processing activities will have to tendentially deal with ores of lower grades and finer intergrowth in the future. Therefore rising comminution efforts will have to be undertaken to liberate the mineral phases on the one hand and to produce functional fillers of high quality and finest dispersity on the other hand. Stirred media mills are very well suited for these two tasks so that it is hardly surprising that the number of stirred media mills in the mining industry is constantly growing. The stirred ball mill "Ana" in the pilot plant of CEMTEC Cement and Mining Technology GmbH is the smallest size of the recently developed CEMTEC Attrition Mill. It is wet operated, equipped with a vertical pin-counter-pin stirrer and has a very beneficial drive power to volume ratio. An extensive parameter study was carried out to determine operational fitness as well as optimum operating conditions. The impact of stirrer speed, solids content, grinding media diameter and grinding media mass on the product fineness of a calciumcarbonate-sample (P80, feed = 42 μm) was examined in particular. Close attention was paid to the product fineness and the mass related consumption of electric energy. This thesis shows that the correct choice of parameters results in very high energy savings.