Andreas Feininger, Production of copper. Interior of large ...
Interior of large ball mill showing the iron balls which grind the ore to a fine size for subsequent treatment by flotation at one of the mills of the Utah Copper Company in Magna and Arthur in Utah, 1940s. Close. Vote. Crossposted by 6 minutes ago. Andreas Feininger, Production of copper. Interior of large ball mill showing the iron balls which grind the ore to a fine size for .