Ore slurry production method and metal refining method

A metal refining method for recovering a metal contained in raw material ores from the raw material ores comprising:

• a pulverizing/classifying step of pulverizing the raw material ores and classifying the resulting ores at a predetermined classifying point so that oversized ore particles are removed so as to obtain a coarse ore slurry composed of undersized ore particles;
• a grain size measuring step of measuring the grain size of the coarse ore slurry obtained by the pulverizing/classifying step;
• and
• an ore slurry condensing step of loading the coarse ore slurry to a solid-liquid separation device and separating and removing moisture contained in the coarse ore slurry therefrom so as to condense ore components,
• wherein in the case when the grain size measured in the grain size measuring step is lower than a predetermined value, one portion of the oversized ore particles that have been removed in the pulverizing/classifying step is loaded and added to the solid-liquid separation device in the ore slurry condensing step.