A method and apparatus of reducing the average particle size of silicon metal particulates employing a liquid oxidant extractant admixed with the silicon metal particulates while the silicon metal particulates are subjected to attrition in an attrition mill. An essentially oxidant-free silicon metal particulate product is produced, with the particulate product having an average particle size within that range of average particle sizes where the silicon metal particulates are susceptible to violent exothermic reaction with an oxidant.