Ore Particle Size Mills Ball mill grind particle size analysis for gold ore Ball mills tumble iron or steel balls with the ore The balls are initially 510 cm diameter but gradually wear away as grinding of the ore proceeds The feed to ball mills dry basis is typically 75 vol ore and 25 steel The ball mill is operated in closed circuit with a Ore Particle Size Mills. Ball mill grind particle size analysis for gold ore Ball mills tumble iron or steel balls with the ore The balls are initially 510 cm diameter but gradually wear away as grinding of the ore proceeds The feed to ball mills dry basis is typically 75 vol ore and 25 steel The ball mill is operated in closed circuit with a