• High pyrite content combined with iron media promotes hydrophilic FeOOH formation on pyrite, improving copper grade.
• Ceramic media prevent excessive FeOOH coverage on chalcopyrite at low pyrite content, preserving floatability.
• Galvanic corrosion current between chalcopyrite and pyrite increases with pyrite content and is amplified by iron media.
• Regrinding media selection should be tailored to pyrite content to optimize cleaner flotation performance.