Mining and Engineering World, Volume 38

amount Ariz assay average bbls body Butte camp Cananea capacity cars coal Cobalt Colo concentrates copper cost Creek crosscut cyanide deposits depth district dividend dredge drift drill duction east East Rand electric engineer equipment field framing furnace grade Hill hoist Idaho increase industry Inst installed iron July Kerr Lake Lake Superior lead lease lode London long tons manganese ment metal Metallurgy Mexico mica miles mill mineral Mont months motor North opened operations output petroleum placed placer mines plant production profit pump pyrites quantity quartz Rand recently reported rock Sept shaft shipments shipped short tons silver smelter smelting South steel stope sulphur tank timbers tion tonnage Tonopah tons Transvaal tunnel United Utah vein week World zinc